SAN FRANCISCO -- Amy Van Dyken, who won four gold medals at the 1996 Olympic Games, was called to testify before the U.S. federal grand jury investigating the BALCO laboratory, it was revealed Thursday.

Van Dyken, now 30, was one of the stars of the Atlanta Games, where she became the only American woman to win four golds at a single Olympiad.

She now has the unenviable honor of being the first swimmer identified in the drugs and money probe that has focused primarily on players from the NFL, major league baseball, and track and field.

Victor Conte, president of the Bay Area Laboratories Co-Operative, and his company have been accused of producing the previously undetectable designer steroid tetrahydrogestrinone, or THG, a charge Conte has denied.

Rob Nelson, Van Dyken's agent and attorney, confirmed that Van Dyken appeared before the grand jury Nov. 13, the same day as sprint star Marion Jones and five NFL players, but said the swimmer had no comment on her testimony.

Nelson also declined to comment on Van Dyken's relationship with Conte.

THG, a synthetic form of testosterone, reportedly has been detected in the urine of five track and field athletes and four members of the Oakland Raiders football team.

Almost all of these athletes have been identified as clients of Conte.

Van Dyken, who reportedly also was a client of Conte's, is a close friend of Bill Romanowski, one of the Oakland Raiders who reportedly tested positive for THG.

Van Dyken became the most popular female athlete of the 1996 Olympics when she won the 50-meter free, 100 butterfly, 400 free relay and 400 medley relay.

Four years later in Sydney, she again won gold as a member of both U.S. 400-meter relays but failed to win a medal in an individual event, finishing fourth in the 50 free.

She also lost public support when she spat in the lane of Inge De Bruijn of the Netherlands before the final of the 50 free, one of three events the Flying Dutchwoman won in Sydney.

Coincidentally, Van Dyken contributed to rumors that De Bruijn had used drugs when she commented that she, too, could win a gold medal "if I were a man."