Fairfax County police believe that they were randomly selected victims and that their slayings were not connected. They were an 18-year-old woman with a broken-down Volkswagen and a couple out for a night with friends. Their killers remain at large.

Sue Baker talks to police regularly and makes frequent visits to the Shirley Highway exit ramp at Backlick Road. On March 29, 1989, in a wooded area next to the ramp, her 18-year-old daughter, Amy, was raped and strangled.

"I've been there a thousand times," said Baker, 40, who lives in Hartwood, Va. "I go back sometimes just to sit at night."

As car after car whizzes by, Baker cannot believe that no one saw anything about 9 p.m. that night, when her daughter's baby blue Volkswagen broke down on southbound Interstate 95 and she apparently set out on foot in search of a gas station.

Police have chased leads and looked at similar cases all along the Eastern Seaboard but have made no arrests in the case, said police spokesman Warren Carmichael.

Baker follows news accounts of similar slayings with sympathy and interest. "I feel so sorry for the people, but I pray, 'Please let {the cases} be related,' " she said.

Baker family members distribute thousands of posters, replacing old ones to reflect a reward that has grown from $10,000 to $25,000 for information leading to an arrest and conviction.

Like the Baker family, relatives of Rachel Raver and Warren Fulton, both 22, are frustrated that there have been no arrests in the deaths of the former George Washington University students. Both were shot; Raver was raped.

Their bodies were found in a field off Hunter Mill Road in Reston on Dec. 6, 1988. The couple was seen leaving Mr. Days Sports Lounge in the District about midnight on Dec. 2.

Investigators believe that the pair was abducted from the District and driven in Raver's car to the field, police said. Witnesses remember seeing the car near the field that night, and one of its doors was open as though someone had been forced out in a hurry, they said.

Raver's car, a brown 1980 Toyota Corolla, was in Queens, N.Y., the next day, but that was not known until two months later, when her mother, Veronica Raver, received a $70 parking ticket in the mail for the vehicle. Relatives in New York have worked to generate interest in the case in that state.

As in the Baker case, Fairfax police have reviewed similar cases for suspects. But the Raver and Fulton case also remains open, and an $11,000 reward is being offered for any information, Carmichael said.