NEW YORK – Sophisticated equipment provided by the Royal Canadian Mounted Police helped identify fingerprints on trash bags that contained body parts of two men killed in the early 1990s in New York. The fingerprints have been linked to a former University of Maine student who was acquitted in Maine of killing another student in the 1970s.

The identification led American investigators to arrest Richard W. Rogers Jr., a nurse from Staten Island, in connection with the murders of computer sales executive Thomas Mulcahy, 58, found at a Woodland Township, N.J., rest stop in 1992, and Anthony Marrero, 44, found in Manchester Township, N.J., in 1993.

Rogers admitted to the 1973 killing of fellow UM student Frederic Spencer, 22, who lived in the same apartment building as Rogers at 10 Main St. in Orono. Rogers claimed the killing was in self-defense, and he was acquitted by a Penobscot County jury.

On Thursday, Spencer’s mother, Louise Spencer, 80, who lives in Mount Desert, Maine, with her husband, Claude, 82, spoke briefly about her son’s death.

“This just renews the pain that we have felt all of these years,” Mrs. Spencer said. “We have been in such pain, and this opens the wound and makes it fresh again.”

She said the death of her eldest son was extremely painful, that “it wasn’t a happy thing for us that he [Rogers] went free.”

The Spencer family was living in Norwich, N.Y., when their son was killed, but has since relocated to Maine.

Mrs. Spencer said it was too difficult for her family to discuss the situation right now.

After being acquitted of Spencer’s death, Rogers, who was a graduate student of French at the university at the time Spencer was killed, said he planned to return to his family’s home in Plymouth, Mass. For the past 20 years he has lived in Staten Island and has worked as a nurse at Mount Sinai Medical Center in Manhattan.

During the early 1990s, police claim, Rogers killed at least two homosexual men and left their dismembered bodies scattered in garbage bags along highways in New Jersey.

Fingerprints are notoriously difficult to lift off plastic surfaces. But with the help of a vacuum metal disposition chamber at the Ottawa labs of the RCMP, 29 clear prints were found on the trash bags, Newsday reported Thursday.

The bags had been stored in a climate-controlled police locker in Trenton, N.J., for eight years because investigators had no means of lifting any fingerprints.

The Canadian department has emerged as one of the premier agencies for lifting prints once thought impossible to obtain.

The state of Maine then came to the aid of New Jersey State Police by running the prints through a computer it recently obtained, called the Automated Fingerprint Identification System, which cross-references fingerprints from jurisdiction to jurisdiction. The results were immediate.

State police in Maine reported that the fingerprints matched those of Rogers, whose prints had been on file in the state since his arrest for Spencer’s death.

Rogers, 50, was arrested Tuesday at the hospital where he worked. He is fighting extradition from New York, and is being held on $1 million bail. He is due in court again June 28.

Police also are investigating whether Rogers may have been linked to at least two other dismemberment murders. The remains of one of the victims were found on the Pennsylvania Turnpike and the other on a highway in Haverstraw, N.Y., in 1991 and 1993, respectively.

The crimes sent a shock wave through the gay community; several of the victims were men last seen in New York gay bars.