Engine Heat May Have Set Off Van Bomb

Agents investigating the method used in last week’s bombing of a van driven by the wife of Vincennes Capt. Will Rogers III have narrowed their suspicions to a crude device that could have detonated the bomb with the van’s own engine heat, federal sources said Monday.

Authorities were still reluctant to link the bombing attack to terrorists, but they confirmed Monday that they were checking reports from witnesses that men acting suspiciously, who appeared to be Middle Eastern, were spotted near the Rogerses’ La Jolla home in recent weeks.

Retaliation Theory

Terrorism is considered a possibility because Iran pledged retaliation after last summer’s downing of a civilian Iranian airliner over the Persian Gulf by the missile cruiser Vincennes, which Rogers commands. Rogers gave the order to shoot the plane down after mistaking it for an attacking Iranian fighter. The downed plane carried 290 people to their deaths.

Last Friday’s bombing is still being treated as “suspected or possible terrorism,” an FBI official said, but other theories range all the way from one or two Iranians acting on their own to disgruntled sailors from Rogers’ ship.

“What if you have one or two Iranians or other followers of the Ayatollah who mount something on their own in response to the Ayatollah?” said one source close to the case in Washington. “Or, what if you have disgruntled sailors on the ship? Not any of this is being ruled out.”

It appears that no breakthrough is imminent, another source familiar with the investigation said.

However, sources said investigators have come to suspect a heat-triggered device after finding no obvious signs of a timer or other form of detonating device. They said the explosion now appears to have been caused by one or two pipe bombs placed under the van, directly below the driver’s seat.

Possibility Wood Was Used

One source close to the investigation in San Diego said theories are centering on the possibility that some type of light wood--possibly balsa--was attached to the bomb and the van’s undercarriage. When the motor heated, the wood could have ignited and detonated the bomb.

He said the wood can be filed down to the size of a match stick or fuse, and that it can be “just taped” to the explosive or engine.

“It’s been done in the past,” he said. “Apparently the CIA and terrorist groups have used it in the past. The wood would get hot enough and burn and this would be the ignitor.”

He also noted that no traces of the lightweight wood would be left after the resulting explosion. Officials at the scene have found small fragments of a plumber’s pipe and end caps, but no clues as to the type of detonating device.

“The bottom line on that is that the leads are zip,” he said.

The Rogerses’ van had been parked overnight in the front driveway. Rogers first drove the van Friday morning to a doughnut shop about three-fourths of a mile from the home. They said he parked the vehicle in front of the shop’s door and turned off the motor. Moments later, he returned home.

About a hour later, Sharon Rogers drove the van about 3 miles before the explosion occurred as she was stopped at a traffic light in La Jolla. She escaped unhurt after leaving the van to investigate what she thought was a bump from behind. Moments after she got out, the van exploded in a fireball and metal fragments tore through the vehicle.

The sources pointed out that the device detonated when she slowed to a stop and the motor began to idle. Normally, an air-cooled engine would be cool as it was being driven, then would heat up as it idled.

Investigators also were checking Monday on reports that as many as three Middle Eastern-looking men were seen in the neighborhood asking for the location of the Rogers home.

“There were a couple of guys who asked a paper boy if there was a captain who lived on the street,” said one law enforcement official. “But the kid had just moved in there and didn’t get much of a description of the men. It happened about a week or two before” Friday’s bombing.

John Petrou, a 22-year-old neighbor who also spoke to the FBI, told The Times that he saw two men he described as Middle Eastern-looking drive into the Rogerses’ cul-de-sac about two weeks before the bombing. Both acted suspicious, Petrou said.

The first man reportedly was driving a gray BMW and drove by on a weekday afternoon when Petrou was outside washing his car, and the second went by a few days later in a Toyota.

“Usually, people that drive through the neighborhood we all know,” Petrou said. “But these were two guys in separate cars, of Arabic descent. . . . I was watching them, but they didn’t look at me. They didn’t look in my face.”

But some officials downplayed the likelihood of the bombers surveying the neighborhood looking for the home. They noted that Rogerses are listed in the phone directory and that the home would be easy to find.

“And nobody’s told us for sure yet that this was an act of terrorism,” one source said.

Identity of Red Car

Officials also on Monday identified the make of the red car seen making a U-turn and speeding from the bombing scene as a Dodge Omni and said that it had been driving behind Sharon Rogers when the van exploded. They also said that as many as four people were reported inside the red car.

“Nobody got a license plate or anything like that,” said one investigator. “And we don’t know that that’s a real connection. It could be somebody panicked when this thing went off.”

Officials also elaborated on a telephone call taken by Sharon Rogers at home shortly after the July incident in which her husband ordered the Iranian jetliner shot down. The caller at that time asked if she was the “murderer’s wife,” then Sharon Rogers hung up.

Afterward, the Naval Intelligence Service placed a tap on her phone, but no other frightening or threatening calls were received.

However, Sharon Rogers did receive a letter, officials said, which, while not personally threatening, did discuss the Persian Gulf incident.

“It was more of a ‘How come these people had to die? Why did this happen?’ but it wasn’t really threatening,” said one source. “And she turned it over to the NIS, too.”

Navy Security Tight

Meanwhile, security remained tight at all San Diego area naval bases. At the 32nd Street Naval Station, where the Vincennes is docked, security personnel checked identification of everyone entering. Sailors leaving the base said they were told to be alert and report all suspicious occurrences or persons.

Two Vincennes crew members leaving the Navy exchange declined to discuss the bombing. The two men said they had been advised that reporters might seek them out.

“We have to be careful what we say, since the FBI still doesn’t know who did this,” said one young sailor.

Officials at Colgate University in upstate New York, where the Rogerses’ son is a student, said Monday they increased campus security after consulting over the weekend with the FBI and naval intelligence. There have been no threats against Will Rogers IV or any other students, according to Lee Pelton, dean of the college.

Access to his residence hall has been limited and security at the campus main gate has been tightened, he said. The school has 2,600 students, and “is small enough that visitors are noticed,” Pelton said.

Times staff writers Jane Fritsch, Ralph Frammolino and H.G. Reza contributed to this story from San Diego. Staff writer Ronald Ostrow reported from Washington.