Blast Rips World Trade Center in N.Y.; 5 Dead, Hundreds Hurt : Disaster: Tens of thousands flee smoky 110-story twin towers. Walls, ceilings collapse into underground commuter train station. Explosion, possibly caused by a bomb, may be work of terrorists.

A tremendous underground explosion believed to be caused by a bomb shook the 110-story twin towers of Manhattan’s World Trade Center on Friday, killing at least five people, injuring more than 600 and sending tens of thousands of workers fleeing for their lives down crowded smoke-filled stairs.

The noon-hour blast blew a huge hole in the complex’s basement garage, collapsing walls and ceilings into a commuter rail station below. Most of the deaths occurred underground, while most of the injuries were due to smoke inhalation in the huge towers.

Nearly nine hours after the explosion, eight disabled people remained in one of the towers, awaiting assistance to the roof so they could be airlifted by helicopter.

About an hour after the explosion, police in New York received a call from someone claiming to represent a group called the Serbian Liberation Front. The anonymous voice said the group had detonated a bomb on the second level of the garage, a fact then only being discovered by rescuers.

“Because a bomb does indeed appear to have gone off on the second level, the claim from the Serbian Liberation Front is credible, or being treated as such,” a ranking U.S. official said.

He said the caller claimed that the purpose of the bomb was to protest U.S. and U.N. intervention in Serbia. The explosion came one day after President Clinton announced that U.S. forces would airdrop emergency supplies to besieged Bosnians, the Serb’s opponents in a bloody civil war.

New York Gov. Mario M. Cuomo said Friday night that “the information I have is it was definitely a bomb.”

The blast did not disrupt subway service, and preliminary inspections found no serious structural damage to the massive towers. But commuter rail service in Lower Manhattan to New Jersey was halted.

The subterranean scene could have been scripted by Dante.

“It was almost like walking through hell,” said Port Authority police sergeant Dan Carbonaro. “It was pitch black with smoke. There were fires all around us. There were a number of cars that exploded and were overturned and burning. One of the levels inside the building had collapsed onto the other. The staircases we normally use to go up and down had collapsed. We were making our way on hands and knees over rubble.”

“You can’t imagine the devastation there,” said firefighter Hank Molle. “You saw cinder block walls that were blown out, ceilings blown out. Then as you went further, you had a heavy smoke condition. We had members who worked down there telling us their co-workers were trapped.” Molle, who with Carbonaro was one of the first rescuers on the scene, said “the rubble in certain areas was high enough it blocked the whole corridor.”

The blast on the B-2 level--the second of six basement levels of the Trade Center--collapsed walls in a locker room and a lunch room. One body was found in the garage. In the locker room, rescuers removed a man with multiple fractures who had to be dug out of the rubble.

“It must have been lunch time and he was going to his locker,” said Molle. “Two bodies were found in the lunchroom area, and there were a bunch of people--12 to 14--who were escorted out of the area who are in the hospital.”

The blast ripped a 180-foot hole in the wall of the underground Port Authority-Trans Hudson train station and triggered a blaze that burned for two hours. The twin towers, the second- and third-tallest buildings in the world, acted like smokestacks, funneling acrid fumes up staircases and vents. An estimated 100,000 employees work in the huge complex near Wall Street.

Outside, hundreds of fire engines, police emergency vehicles and ambulances choked streets surrounding the Trade Center. Streams of smoke-blackened and shaken office workers emerged from the towers telling stories of heroism and terror.

The task facing firefighters and police was complicated. Many workers still were trapped hours after the blast in offices high in the towers and on the roofs. Others, including asthmatics and people with heart conditions, waited to be rescued in upper floor offices, while physicians treated the injured. Firefighters carried some of the sick down the stairs in stretchers and baskets. All power was knocked out in the Trade Center, stranding hundreds in elevators.

At least seven elevators stalled between floors with people in them. For a time, 250 people were trapped in one of the Trade Center’s cafeterias.

Police officers in a helicopter plucked a pregnant woman from the roof of the towers. Two tours of elementary schoolchildren were trapped for hours on the Trade Center’s observation deck. As darkness fell, rescuers debated the best way to remove those who were stranded on the roof of the buildings. They eventually climbed down 110 flights of stairs.

Commercial radio stations in New York broadcast appeals for people still trapped to remain calm.

Many of those fled the building without their overcoats and pocketbooks into snow squalls and bitter cold. The Red Cross set up an emergency shelter at the World Financial Center directly across the West Side Highway from the Trade Center.

“Within five minutes on the 104th floor there was smoke coming out of the elevator shafts,” said Larry Bianculli, 31, a consultant for a data communications firm. “We started down the fire stairs and we got to 69 and the lights went out and we had to feel our way down. It was just volume all the way down--people. There were a lot of women, and some pregnant women, and some older women and everybody started feeling for them.”

“I was sitting in my office and there was a huge boom and the whole building shook. It was like thunder,” said Kathleen Connors, a market researcher, as she sat wrapped in a blanket in the Red Cross shelter. “Things just started falling off the walls. I went down to the hallway and smoke just started pouring in. It took us two hours to get down from the 86th floor.”

Hours after the explosion, police evacuated the Empire State Building in mid-Manhattan after a bomb threat. No explosive device was found.

Senior U.S. counterterrorism officials said the blast was probably caused by a car bomb that went off in the underground garage, serving both buildings of the Trade Center.

“This is the most sophisticated terrorism attack against the United States since the bombing of Pan Am 103,” one law enforcement official in Washington said. That bombing over Scotland in 1988 killed 270 people.

Intelligence officials indicated that they had not heard of the Serbian Liberation Front, which claimed to have planted the bomb, and were investigating all possibilities. One anti-terrorism expert familiar with the investigation noted: “In many cases, the pros don’t claim it (the bombing).”

Anti-terrorism experts in New York said their investigation was being hampered by the huge crater and the possibility that highly toxic asbestos was in the area.

The New York field office of the Secret Service and the office of Gov. Cuomo are situated in the World Trade Center complex. Cuomo was in Albany. The Secret Service parks its fleet of cars in the garage, where the explosion occurred. Three agents were injured and several cars were damaged. None of President Clinton’s official limousines were in the garage at the time.

At St. Vincent’s Hospital and other area medical centers, wailing caravans of ambulances created traffic jams outside emergency room loading docks, double- and triple-parked waiting to discharge the injured and return for more.

The effects of smoke inhalation were the most common symptoms. Most of the more than 100 patients transported to St. Vincent’s arrived clutching oxygen masks as they were whisked from the frigid curbside entry.

Inside, a steady stream of nurses rushed through the corridors pushing carts, each filled with a dozen green oxygen canisters. White-jacketed orderlies dispatched to round up urgently needed gurneys and wheelchairs cheered each other for each unexpected discovery.

Some of the injuries were more severe--a fractured skull, a fractured hip, a firefighter with multiple injuries from a 20-foot plunge.

At 2:30 p.m., a man with severe chest injuries arrived in cardiac arrest. Efforts to revive him failed and he was pronounced dead. Dr. Lambert King, St. Vincent’s medical director, said the still unidentified man “had a crushed chest, indicating that something must have fallen on him.”

As Dr. King spoke to reporters in the hospital waiting room, a number of ambulances raced past the window near his podium, delivering more victims. For a time they were arriving at a rate of about one victim every two minutes.

A special waiting area was created in another section of the hospital to accommodate dozens of family members who began arriving to be with injured loved ones. Access to the hospitals was hindered by numerous closed streets and crowds of gawkers that compounded normally difficult Friday afternoon traffic problems throughout Lower Manhattan.

The twin towers that dominate the skyline of Lower Manhattan are a vertical community bigger than Santa Monica or Newport Beach. The first hints of trouble prompted little more than curiosity from some.

Rose DeMaio was in the cafeteria on the 43rd floor waiting to have lunch with her sister, Grace, when the floor shook. It was just a sudden jolt, then it was over.

“Some people went to the window and said they saw black smoke coming out of the bottom of the building. . . . Then my sister showed up and started to have her lunch,” said DeMaio, a 36-year-old administrative assistant for the Port Authority. “But I had a feeling that this was something serious. All of a sudden a woman started screaming.”

There was smoke in the elevator shafts--smoke coming up the escalators. The lights flickered. DeMaio, her sister and several other women from the cafeteria plunged into a stairwell and started the long, harrowing trek down.

“The stairwell was terrible. It was very smoky. We were hacking. We wiped ourselves with tissues and tried to keep things over our faces.”

More than 60 floors up, in the posh penthouse restaurant, Windows on the World, Robert Rose, 24, of San Diego was listening to a luncheon speaker when he felt what seemed like a mild earthquake or a clap of thunder.

Even when someone came over to announce the restaurant was being evacuated, he said there was no panic. In fact, when told that they would be hiking down more than 100 floors, some of the luncheon guests were inspired to start singing: “One hundred bottles of beer on the wall. . . . “

Almost immediately the mood changed. In the dimly lighted stairwell they encountered the first scent of danger.

“There was a lot of smoke and we stopped,” Rose said. “No one knew what was going on and the people who were leading us turned around and went back up. We decided to keep going down, but there was more smoke, a lot of smoke. People started getting nervous.”

Halfway down the stairwell, Rose said, the lights went out.

“That’s when everybody got very nervous. We couldn’t see. We didn’t know if we should continue walking down. But people calmed down pretty quickly and we just grabbed onto the person in front of us and we formed a human chain.”

Rose, who was attending a brokerage training program for his new job at Dean Witter, shivered in the cold as he described what was supposed to be “the big kickoff to our new careers.”

In the basement, firefighter Tim Kelly said “there was a tremendous amount of damage to the building. We had fire burning through the floor. We had a tremendous hole in the floor and a lot of walls blown down on B-1 and B-2 levels.”

“The floors dropped on the cars,” added Jeff Mulligan, another firefighter. “It was a heck of an explosion.

“It was very smoky . . . to go down into the smoke is a scary feeling. You are going into the unknown. You walk around your house with your eyes closed, you feel a little something in your chest. You are not comfortable with it. You go into a building you don’t know and there is fire all around you and a smoke condition--it is a really scary feeling.”

Law enforcement officials in Washington theorized that a car could have carried plastic explosives into the garage. These officials said that threats had been received Friday morning against the U.S. Embassy in Vienna from a group calling itself the Serbian National Party, complaining that the international embargo against Serbia had halted close to 100 trainloads of steel and warning of severe consequences, including deaths.

Plastic explosives have long been the bomb material of choice for terrorist groups. It is a clay-like substance that is easily concealed and safe to carry. It does not show up on airport metal detection machines, it can be molded to look like harmless objects and it can only be detonated by a standard blasting device.

In the United States, an explosive called C4 is manufactured almost exclusively for military use and possession of surplus supplies by civilians is supposed to be tightly regulated. Among its possible civilian uses are to assist oil drilling, to clear rocks for road or tunnel construction, underwater demolition and the controlled demolition of buildings.

It is extremely powerful. An explosives expert with CIA ties once boasted to The Times that with little more than 100 pounds of C4, strategically placed, he could “bring down the Empire State Building.”

Times staff writers Robin Wright and Ronald J. Ostrow contributed to this story from Washington.

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Terrorist Acts on American Soil

U.S. counterterrorism authorities said they believe the World Trade Center explosion could have been caused by a bomb. Here is a list of some previous terrorist acts in the United States:

Jan. 20, 1991: Los Angeles County sheriff’s deputies take Shaker Famy Rezk into custody on suspicion of telephoning a sheriff’s substation to announce that he had placed a bomb on a plane bound from Los Angeles to the Middle East.

April 12, 1988: Yu Kikumura, an alleged Japanese Red Army member, is arrested at a New Jersey Turnpike rest stop after state troopers find explosives, timing devices, detonators and other materials in his car.

Oct. 23, 1987: Three Lebanese-born Canadians--Walid Kabbani, Georges Younan and Walid Mourad--are arrested in Vermont for carrying a bomb. It was the first known arrest of alleged Middle East terrorists carrying explosives in the United States.

Oct. 11, 1985: A bomb rigged to the front door of the Arab-American Anti-Discrimination offices in Santa Ana kills Alex Odeh, the group’s western regional director.

May 19, 1981: Two bombs were safely removed from the U.S. Mission to the United Nations and the Honduran Consulate. The Puerto Rican Armed Resistance claimed responsibility.

Jan. 23, 1981: Bomb explodes at the State Supreme Court building in Manhattan. A Croatian terrorist group and Puerto Rican terrorist group, FALN, both claim responsibility.

Oct. 6, 1980: The Bel-Air residence of the Turkish consul general is firebombed by an Armenian terrorist, who was later convicted of the crime.

March 9, 1977: Members of the Hanafi Muslims seize three Washington buildings and hold 134 hostages for almost two days before surrendering.

Aug. 3, 1977: Puerto Rican terrorists bomb two New York office buildings, killing one and injuring seven.

March 21, 1977: Puerto Rican terrorists bomb the New York City headquarters of the FBI. One person is injured.

Jan. 24, 1975: Puerto Rican terrorists claim responsibility for an explosion in New York’s Wall Street district, killing four people and injuring 53 others.

March 1, 1954: Four Puerto Rican nationalists fire 30 shots from the U.S. House visitors’ gallery, wounding five congressmen.

Nov. 1, 1950: Two Puerto Ricans, Griselio Torresola and Oscar Collazo, attempt to assassinate President Harry S. Truman at Blair House in Washington. Torresola is killed and his partner and three police officers are wounded.

Source: Compiled by Times researcher D’Jamila Salem