Car Bombing Investigation Shelved : Mystery: Sources say it may never be known who planted device in van of ex-skipper of ship that shot down Iranian airliner. Terrorism largely ruled out.

SAN DIEGO —  Authorities have shelved an investigation into the bombing of a van belonging to Navy Capt. Will Rogers III, former skipper of the guided missile cruiser Vincennes, and have all but ruled out the possibility that terrorists planted the bomb two years ago, sources have told The Times.

Sources in Washington and California said investigators remain unable to develop a lead solid enough to support charges in the bombing.

Sources also confirmed what they had hinted at before--that terrorism essentially has been discarded as a working theory in favor of the notion that the attack was the result of a personal grudge against Rogers or his family.

Because the March 10, 1989, attack was aimed at a van owned by Rogers, it whipped fears that international terrorism had arrived on U.S. soil, and it sparked an intensive investigation by the FBI, Naval Investigative Service in San Diego, the Bureau of Alcohol, Tobacco and Firearms and, to a lesser extent, San Diego police.

Rogers’ wife, Sharon, who was alone in the van at the time of the bombing, escaped injury.

Investigators believed the bomb may have been planted by Iranian extremists seeking to avenge Capt. Rogers’ order in July, 1988, aboard the Vincennes, to shoot down an approaching Iranian airplane that turned out to be a civilian jetliner. Two-hundred and ninety people were killed. Rogers eventually was exonerated because the airliner had failed to respond to repeated warnings from the Vincennes.

Mike Bourke, assistant director of the Naval Investigative Service office in San Diego, said the case was still open. “The investigation is still pending, and I have no additional comment,” he said.

FBI spokesman Ron Orrantia in San Diego did not return repeated phone calls to his office.

The prosecutor on the case, Assistant U.S. Atty. Larry Burns in San Diego, declined to comment.

However, four sources familiar with the investigation have told The Times of the virtual halt in the probe. They also stated more emphatically than they have in the past that the focus of the case has shifted away from suspicion of terrorism.

The sources asked to remain anonymous, saying that the last flurry of press reports on the case--around the first anniversary of the bombing--launched an intense internal drive at federal and Navy agencies to find out who had talked to reporters.

The sources said that, since the intensity of the investigation has slackened significantly, it is unlikely the case ever will be solved.

They added that virtually no work has been done since last spring.

It has been 18 months since a federal grand jury in San Diego issued subpoenas in the case and there’s no indication an indictment is near, sources said.

The case has gone on for so long that some rewards for information no longer exist, said Laurie Weitzman, associate director of the Crime Stoppers tip hot-line program in San Diego.

“It’s one of those very frustrating crimes,” one source said. “But it’s not at all unique. It’s not unique that some crimes remain unsolved for very long periods of time or never get solved. Who killed Jimmy Hoffa?”

Although investigators hope for new leads, Will Rogers, who now teaches Navy tactics, said in a recent interview that he and his wife are trying to put the whole thing behind them.

“We’re trying to rebuild our lives, and I don’t see any point in revisiting this,” Will Rogers said.

Because of concerns about terrorism, Sharon Rogers was dismissed within weeks of the bombing from La Jolla Country Day School, where she had taught for 12 years.

Unable for months after that to land a full-time job, she is back at work this school year, teaching at a northern San Diego County school, according to a friend of the family who asked to remain unnamed.

Nearly two years after the incident, after tracking countless tips, the FBI has not determined why the Rogers’ van was attacked, sources said. The FBI assumed jurisdiction of the case only because of the possibility of terrorism and, at one time, ranked the bombing as one of its top priorities, they said.

In late 1989, The Times reported that the investigation was turning away from terrorism and attention was being focused on two American men, brothers with ties to Southern California.

Investigators zeroed in first on H. George Marxmiller, an out-of-work Eastern Airlines pilot who was in the midst of a bitter divorce. Will Rogers was listed as a witness in the Georgia divorce case, though the divorce was concluded without Rogers’ testimony.

Marxmiller contacted the FBI in 1989 with allegations that Will Rogers was involved sexually with a friend of Marxmiller’s wife. Marxmiller alleged that the affair provided Will Rogers with a motive to kill Sharon Rogers.

Rogers has said repeatedly that he has no clue why his name surfaced in the divorce case and has consistently declined to respond to Marxmiller’s accusations.

Sources said Marxmiller failed a lie detector test about his knowledge of the bombing, prompting investigators to consider him a suspect in the case.

Marxmiller told investigators that he visited his brother, Tom Marxmiller, who was then living near Los Angeles, about two weeks before the blast.

That angle remains the most promising, sources said in recent interviews. But it has not panned out.

George and Tom Marxmiller said in separate phone calls, as they have many times before, that they know nothing about the bombing.

“Like I say, I feel like I’ve been accused, but I haven’t really had the right to defend myself,” said George Marxmiller, 49, who flies for an airline based outside the country.

“And I don’t think I should have to defend myself,” he said. “I know I didn’t do it, and I know my brother didn’t do it.”

Times staff writers Ronald J. Ostrow in Washington and Richard A. Serrano in Los Angeles contributed to this story.