Her body was found in a wooded area south of the Long Island Expressway in North Shirley, about 17 miles east of where she had last been seen, entering a small blue car outside the Blue Dawn Diner in Islandia.

She was Colleen McNamee, 20, and she had been brutally beaten and strangled.

Two months earlier, in November 1993, another young woman, Rita Tangredi, 31, who, like Ms. McNamee, was believed to be a prostitute, had been killed nearby, her nude body posed the same way as Ms. McNamee’s.

Twenty years before sections of beachfront brush on Long Island became a dumping ground for prostitutes’ bodies, these two unsolved murders staggered the victims’ relatives and friends, leaving a trail of devastation that friends say included the suicide of Ms. McNamee’s boyfriend.

Now, forensic work by the Suffolk County Police Department, along with changes to DNA collection procedures, have brought some long-delayed relief to family and friends: John Bittrolff, 48, a carpenter and married father of two from nearby Manorville, was arrested last month on charges of murdering Ms. McNamee and Ms. Tangredi.