When Jonathan Jay Pollard was a Stanford University undergraduate a decade ago, his friends discovered a phenomenon they labeled "the Pollard factor."

"It meant you had to discount a lot of what he said," a close friend said, recalling Pollard's stories about serving as a colonel in the Israeli army and working for the Mossad, the Israeli intelligence service.

On the other hand, the friend said, "there was always a kernel of truth to most of Jay's stories."

The eccentric undergraduate who captained food fights as if they were military campaigns went on to become a civilian Navy intelligence analyst with top secret security clearance and access to the most up-to-date information about international terrorist activity.

Now, "the Pollard factor" has resurfaced with a vengeance. Pollard, 31, was arrested last week on charges of spying for the Israeli government. His wife of four months, Anne L. Henderson-Pollard, was arrested the following day. The alleged espionage and its bitter aftermath have strained relations between the United States and Israel, one of its closest allies.

Pollard initially told federal agents who questioned him that he was spying for the East Germans and the Pakistanis, in addition to supplying intelligence information to the Israelis, according to sources familiar with the investigation. Investigators have found nothing to support his claims about East Germany and Pakistan.

"When I heard on the radio that he said Israel and Pakistan, I said, 'Man, that's another Pollard story,' " said a roommate of Pollard's at Stanford. "Those were his two theme stories for years."

Like many of Pollard's stories, however, this one also may well contain at least some kernel of truth: Both Israeli and U.S. officials say that Pollard was involved in some way with Israeli intelligence operatives.

Pollard has told the FBI that he has been spying for the Israelis for about a year and a half, that he turned over classified U.S. documents to Israeli representatives in Washington and that he was paid $2,500 a month in cash, an FBI agent testified this week.

Interviews with friends of Pollard paint a portrait of a brilliant yet troubled man who from an early age was mesmerized by politics and the shadowy world of espionage, and fantasized about becoming one of those at the center of power.

Born in Galveston, Tex., he grew up in South Bend, Ind., where his father, Morris Pollard, a noted microbiologist, heads the Lobund Laboratory at Notre Dame.

Friends at Stanford describe him as smart and funny, obsessed with politics in any form although his own politics were decidedly conservative. Pollard, they said, was an aficionado of playing intricate "war games" that often stretched through the night.

Passionate about Israel, he told friends that once, while on guard duty on a kibbutz there, he had killed an Arab. Another time, he said he was upset because most of the Israeli friends he had trained with had been killed during the Yom Kippur War.

Pollard's roommate said he once told Pollard about a high school escapade in which the roommate, the manager of his school basketball team, had sent himself a telegram and signed it Wilt Chamberlain. Pollard, he said, then sent a telegram to himself, addressing it to a "Colonel" Pollard.

"Jay wanted to live his life like it was a novel instead of his life," said another college friend.

After leaving Stanford, Pollard enrolled at the Fletcher School of International Law and Diplomacy of Tufts University.

Students who knew him there described Pollard as a "loudmouth" given to boasting about everything from his exploits with women to ties with the South African intelligence service.

Pollard's penchant for stories that seemed to stretch the truth remained after he began work for the Navy in 1979.

His resume listed a job at the Institute for Foreign Policy Analysis in Cambridge, Mass., but institute director Robert Pfaltzgraff said Pollard was never employed there.

Since June 1984, Pollard has worked in Suitland as a civilian counterterrorism analyst at the Navy Investigative Service. He was earning about $33,000 a year when he was arrested, according to the FBI.

In September 1984, he accosted former representative John LeBoutillier (R-N.Y.) after a speech at the conservative Heritage Foundation about American prisoners of war in Vietnam.

"He flashed his Navy credentials at me and I thought, 'Gee, I'm getting arrested or something,' " LeBoutillier recalled.

He said Pollard told him that the Navy had information about prisoners of war still in Vietnam, and in later discussions, mentioned secret missions involving "freedom fighters" in Afghanistan and Cambodia.

LeBoutillier said he became suspicious about Pollard, however, after Pollard claimed to have attended graduate school at Harvard but was not listed in the alumni directory.

Pollard boasted to friends earlier this year that he was part of a team assessing damage done by the Walker family spy ring -- an assignment that Navy spokesman Lt. Stephen Pietropaoli said Pollard never had.

According to a Defense Department source, Pollard's security clearance was temporarily withdrawn in 1981 for "bizarre behavior." Navy spokesman Kendell Pease said it would be inappropriate for the Navy to comment on the case while it is under investigation.

Dale Hartig, a spokesman for the Defense Investigative Service, which conducts background checks for Defense Department employes, said the normal investigation of Pollard for a top secret security clearance would have focused on the preceding five years of his life and included interviews with friends.

He said that Pollard, as a civilian employe, would not have been interviewed personally, although military employes are questioned directly by investigators.

"The fact that Jay boasted about working for Israeli intelligence made him unsuitable for working for naval intelligence," said Jonathan Marshall, editorial page editor of the Oakland Tribune and a classmate of Pollard's at Stanford.

Hartig said he could not comment on the adequacy of the Navy's background check of Pollard.

In contrast to Pollard, his wife Anne was much more quiet and kept to herself in her job in the public relations office at the National Rifle Association, according to NRA spokesman John Aquilino.

When Henderson-Pollard left the NRA earlier this year to work as a free-lance sales representative in Washington for CommCore, a New York public relations firm, he said, "I encouraged Anne to be more outgoing."

An FBI agent testified this week that Pollard twice called his wife during an interview several days before his arrest and instructed her to remove their wedding pictures and a "cactus" from their Dupont Circle apartment.

The FBI later learned that "cactus" was the abbreviation for a weapons system depicted in documents contained in a suitcase that Henderson-Pollard delivered to an unidentified friend within minutes of the calls from her husband, according to agent Eugene J. Noltkamper. The agent said that Henderson-Pollard told the friend that the suitcase, which the FBI later seized, contained documents that she was going to use in a presentation at the Chinese embassy.

Karen Berg, an owner of CommCore, said in an interview that Henderson-Pollard helped set up a public relations pitch CommCore made to officials at the Chinese Embassy in Washington on Sept. 30, long before the suitcase was confiscated.

Berg said CommCore was trying to persuade the Chinese to hire the firm to help train embassy officials in public relations techniques, but the firm was never hired. Berg said the firm's contact with the Chinese had nothing to do with the Pollards' current troubles -- a statement confirmed by an official familiar with the investigation.

Berg said she agreed to have Henderson-Pollard represent the firm in Washington as a favor to her father, Bernard R. Henderson, a longtime friend and veteran Washington public relations man. Berg said the young woman struck her as ambitious and "a go-getter."

Berg said Henderson-Pollard was "very proud" of her husband.

One friend who had known Pollard since college said she was not stunned by news of his arrest. "I just thought, 'There's Jay for you.' It didn't surprise me at all."