Bomb Arrest Warrants Issued : Death Toll at 52; U.S. Offers $2-Million Reward : Terrorism: Unidentified suspects are linked to a rental truck used in Oklahoma City blast. FBI officials provide descriptions of the two white men sought.

The U.S. government Thursday offered a $2-million reward for information leading to the conviction of the Alfred P. Murrah building bombers, and the FBI issued warrants for the arrest of two unidentified white men. Rescuers probed wreckage for survivors, and deaths climbed to 52--with expectations that they would exceed 200.

The reward was announced in Washington by Atty. Gen. Janet Reno, who asked at a nationally broadcast news conference that anyone with information about the bombers telephone the FBI. She said that the reward money was being contributed by a variety of federal agencies. Most of it, she said, would come from the Treasury Department.

At a news conference here, Weldon Kennedy, in charge of the FBI investigation in Oklahoma City, said the two warrants were issued for men “associated with” a rented truck used in the bombing. He said they were “John Doe” warrants because the FBI did not know the identities of the two men, but he released composite sketches of the pair and described them as:

* White, medium build, 5-foot-10-inches or 5-foot-11-inches, 180 to 185 pounds, light brown crew cut, right-handed.

* White, medium build, 5-foot-9-inches or 5-foot-10-inches, 175 to 180 pounds, brown hair, tattoo visible beneath T-shirt sleeve on left arm; possibly a smoker.

Kennedy said that a third man, whom Reno described as a “possible witness,” was being returned from London. Britain’s Home Office said the man had landed at Heathrow Airport on a flight from Chicago and was being sent back to the United States. Neither the Home Office nor the U.S. Justice Department offered any additional information about him.

There were these additional developments:

* The death toll reached 52 when rescue workers removed additional bodies from the wreckage of the federal office building late in the day. The rescuers had suspended their search until the shattered columns of the building could be reinforced with concrete and steel. One doctor told reporters that the structure was a “cave filled with booby traps.”

* President Clinton, using ever harsher words about the bombers, portrayed their deed as a threat to national security. “Make no mistake about it,” he told a news conference in the White House Rose Garden. “This was an attack on the United States, our way of life and everything we believe in.” He further tightened security in federal buildings.

At his Oklahoma City news conference, Kennedy said the FBI considered its two suspects “armed and extremely dangerous” and cautioned that “citizens should not attempt to take any action against these men.” Instead, he said, they should provide information about the suspects to the nearest FBI office, or call 1-800-905-1514.

A federal law enforcement source in Washington said authorities were able to obtain descriptions of the two men by locating an identification number on a truck axle found two blocks from the wreckage of the building. Investigators traced the truck to a Ryder rental office in Junction City, Kan., the source said.

At the rental office, said the source, who asked to remain anonymous, investigators were able to piece together descriptions of those involved in the rental. Kennedy said the truck was used to transport several thousand pounds of fertilizer and fuel oil to the front of the building.

The deadly mixture was detonated at 9:04 a.m. Wednesday, when hundreds of office workers were at their desks and many of their children were in a second floor day-care center. Kennedy said the fertilizer and fuel oil were touched off with a “low-order” incendiary device.

He declined to describe the exact type of truck used to carry the explosives. But other investigators said that it would have had to be a large truck or van. They said the amount of fertilizer and fuel oil capable of such an explosion could not have been transported undetected in an open-bed pickup truck.

Kennedy said the man held in London and returned to the United States appeared to be carrying a U.S. passport. British authorities said they detained him at Heathrow on information supplied by U.S. Customs. He was flown to Washington under escort, where he will be questioned by the FBI.

A Heathrow security source said the man was in his early to mid-20s, of Arab appearance, with jet black hair and mustache.

The man was believed to be planning to fly on to Rome when he was refused admittance by the British authorities. A federal law enforcement source said the witness may be linked to three pieces of luggage that Italian authorities seized in Rome after they were flown in from Chicago.

One U.S. source said the luggage included possible bomb-making tools and materials. But Carl Stern, the Justice Department public affairs director, refused to confirm or deny it.

At her press conference, Reno was asked if the composite drawings of the two suspects linked to the rented vehicle made it fair to conclude the suspects were not of Arab origin.

“I don’t think that you should conclude anything until the evidence is in,” she said. “We are trying to pursue every lead. It is important that the people of this country not be confused by any conclusion that is not based on solid fact.”

A spokesman for the Immigration and Naturalization Service in Washington denied that the INS had made any arrests linked to the Oklahoma City bombing, knocking down widespread media reports that it was holding three suspects of Middle Eastern extraction in Dallas and in Oklahoma.

The INS spokesman said flatly that the agency does “not have any individuals in custody pertaining to the Oklahoma City bombing case.”

The INS is deeply involved in the case, however. The agency has assigned a veteran of the 1993 World Trade Center bombing, Dan Malerio, head of investigations for the INS New York district office, to the FBI group working on the Oklahoma City case.

In addition, the INS has assigned a team of agents to Oklahoma City, while INS port directors are working with airport officials around the nation to mount an intensive screening of airline passengers departing the United States.

The Search

Throughout the day, grim firefighters and K-9 teams filed in and out of the Murrah building, where they focused all of their efforts probing pockets or voids in the pancaked structure for anyone who might still be alive.

“Firefighters are having to crawl around some bodies still in the area,” said Assistant Fire Chief Jon Hansen. “The only time we’re taking out a body is if it’s in the way. We’ve got to focus on the possibility that there’s still people living in there.”

But the rescue crews, relying on high-tech audio sensors and fiber-optic cameras, did not pick up any signs of life.

On several occasions, the rescuers were ordered out of the rubble so that demolition crews could remove concrete and steel reinforcing rods that threatened to collapse on them. At one point, all rescue work was halted briefly so that builders could reinforce parts of the building with steel and concrete.

“Right now, it’s very, very slow,” Hansen said. “We have to be so careful.”

Pieces of rubble continued to fall, however, ricocheting through the structure every time a strong wind blew. An air-conditioning unit, hanging from its wire connections, swung precariously from the sheared face of the building, clanging against the cement.

The rescuers dug with shovels, lifted cement slabs with crowbars, smashed concrete with sledgehammers and sifted rubble with their gloved hands. They wore hard hats, knee pads, goggles and helmet lamps.

In dusty darkness inside the wreckage, they pressed masks firmly against their mouths and noses. “It was the smell of death, basically,” said Danny Hague, an 18-year veteran of the Fire Department.

Asked about the possibility of finding anyone alive, rescuers talked hopefully about stories of miraculous survival following earthquakes in San Francisco, Mexico City and the Philippines. But their optimism was tempered by the hard reality of body parts, splattered blood and children’s toys.

The rescuers were led through brief counseling sessions before entering the structure to prepare them for the horrors inside. When they came out, they went through more counseling sessions to talk about ways of dealing with what they encountered.

“It can sure mess a guy up seeing all that stuff,” said Steve Capps, a firefighter for 16 years. “What you see in there is not normal.” He focused most of his efforts on what was left of the day-care center.

He paled, he said, at the sight of only one item: a diaper.

“It really makes you want to go home and hug your kids,” Capps said. He is the father of two boys, ages 11 and 16.

For Fire Department Lt. Tommy Thompson, it was a baby’s white shoe.

He spotted it in the rubble of the basement, put it in a plastic evidence bag and had it taken out of the building. “It was a shoe, just a little kid’s shoe,” said Thompson, a fourth generation firefighter. “It just brings back that there were kids--that there still are kids--in there.”

At one point, speculation swirled about a woman many rescue workers believed they had seen waving for help from a ledge on the 8th floor of the nine-story building. But after surveying the ledge with high-powered binoculars, Fire Chief Gary Marrs concluded that it was “a piece of furniture, not a human body.”

President Clinton

In his remarks, Clinton added a veiled warning to any foreign government that might be linked to the bombing.

While cautioning that there is no proof so far that foreign powers were implicated, he said that “whoever did it, we will find out, and there will be justice that will be swift and severe. And there is no place to hide.”

Clinton, who also ordered that flags be flown at half-staff, expressed satisfaction that the crime bill proposed by his Administration included provisions for capital punishment in bombing cases such as this.

“If this isn’t an appropriate case for it, I don’t think there would ever be one,” he declared. When Reno announced Wednesday that she would seek capital punishment for the bombers, Clinton said: “She did so with my knowledge and support.”

The President also urged Americans not to “jump to any conclusions” about the ethnic origins of the perpetrators. He noted that three Arab American groups had condemned the bombing.

In Washington, officials moved temporary barriers into place along roadways and increased auto searches and traffic surveillance.

Katz reported from Oklahoma City and Ostrow from Washington. Times staff writers James Risen and Paul Richter in Washington, Richard A. Serrano in Oklahoma City and J. Michael Kennedy and Richard E. Meyer in Los Angeles also contributed to this story.