Carol Lynn Drewer, the Northern Virginia banker's daughter who was abducted Tuesday and then freed for a $50,000 ransom, had been the victim of a similar, but unsuccessful kidnap attempt earlier this year, an informed source said yesterday.

The source said a lone male was involved in the earlier attempt, which was not made public at the time. Law enforcement officers refused to confirm or deny yesterday whether the first incident occurred, or if it did, whether the two attempts were related.

Sources close to the Drewer family yesterday expressed surprise that the 19-year-old Drewer should be the target of two kidnap attempts since, one said, her family "is not as wealthy as some other bankers."

Drewer's father, Milton Lee Drewer jr., is president of First American Bank of Virginia where his daughter is employed in the marketing department. The Bank's headquarters are at Tysons Corner, where the kidnaping took place.

Authorities said earlier that telephoned ransom demands during Tuesday's abduction were made by "a muffled male voice," but the FBI has refused to rule out the possibility that more than one kidnaper was involved.

The FBI and police yesterday said they have no suspects in the case.

Additional details about the case emerged slowly yesterday as the FBI and police from Arlington, Fairfax and Alexandria continued their investigation.

Drewer, a former student at Northern Virginia Community College, apparently was accosted by a lone man as she arrived for work between 8 and 9 a.m. in the bank's parking lot and forced back inside her car.

Bound and blindfolded, she as driven away in her own car. But a source said yesterday she was later transferred to the kidnaper's car in the bank parking lot. Police subsequently found Drewer's car parked in the lot.

During the day, the source said, Drewer was driven by the abductor to several First American Bank branches in Fairfax County where she wrote "one or two" checks on her own bank account, presumably to give to her abductor.

Special agent Larry York, in charge of the FBI's Alexandria field office, declined to comment. "I can say that the fact that she had been kidnaped was not known until late in the afternoon, after the abductors made their first telephone call," he said. "Until that first telephone call, there was no indication of an abduction. She had simply not shown up for work."

Sources close to the family said they were baffled that Drewer -- who is said to be a fine athlete and a good swimmer -- did not resist. Neither federal nor local authorities have disclosed whether the kidnaper was armed.

Police also seemed hampered by an apparent lack of witnesses to the initial hours of the kidnaping, especially since Drewer would have been untied, and her blindfold removed, in order to write and present checks to bank employes.

During the morning hours, the source said, Milton Drewer and his wife were in Charlottesville for a conference and were not summoned back until the afternoon by bank officials.

The source indicated that by Tuesday night the elder Drewer was in contact with the captor or captors via a telephone in his car, and investigative sources said that Drewer himself made the payoff, near the bank where the abduction orginally occurred.

Some time between 11 p.m. and mid-night, authories said, Carol Drewer was dropped off near a 24-hour convenience store a short distance from the Southern Towers apartments at the Seminary Road interchange with Shirley Highway. The source said that the abductor gave Drewer 20 cents for a telephone call, and that FBI agents subsequently drove her home.

There were reports yesterday that the FBI had somehow been involoved in an unsuccessful attempt to monitor the ransome payoff. York vigorously denied this, stating that the FBI had respected the family's request that its agents not interfere with the payoff.