PHILADELPHIA (AP) _ For years, two fingerprints sat unexamined in separate police files. One had been found 18 years ago at the scene of a grisly double slaying. The second, investigators said, was on an arrest record for a man who lived in the neighborhood where the killing took place.

Acting on a tip, investigators matched the two this week.

Brett Reed, 47, was arrested at his home Wednesday and charged with killing a woman and her son during a robbery in 1985. The decomposing bodies of Delores Bryant, 50, and John Bryant, 34, were found in the basement of their row house days after their deaths.

One of the few clues to the killings was a fingerprint found at the scene. But, in the days before computer databases were commonplace, detectives were unable to match the print to a suspect.

Investigators on Thursday said they took another look at the print when they got a tip from someone who suggested Reed as a suspect. They matched the crime scene print with an old police record containing Reed's fingerprints.

Police Capt. Richard Ross wouldn't identify the source of the tip, or describe the information the person provided, other than to say that it ``led us in the right direction.''

Reed was in custody Friday. It was unclear whether he had an attorney. The public defender's office in Philadelphia said it was not yet handling Reed's case.

The arrest is the second ``cold case'' bust this summer for the department.

In July, police arrested a man on charges that he raped and strangled a 10-year-old girl in her bed 16 years ago while her family slept. In that case, a longtime suspect confessed after a new DNA test on blood and hair samples he gave investigators in 1988 proved to be a match with sperm found on the victim's body.