"Mutilation of books is a terrible problem in all libraries, and this is one of the worst I've ever seen," Verba said. "I'm relieved that if this is indeed the person, he'll be off the streets."

Rooney said the investigating officers--Sgt. Kathleen Stanford, Det. Richard Mederos, Det. Richard De Cruz, and Det. Paul Westlund--were able to discover little about Womack's past.

They said he had previously worked at a nursing home in Littleton, Mass. He had spent time in the Phoenix, Arizona, area before that.

The Boston Herald reports today that Womack discovered the body after his father committed suicide 20 years ago. The Herald also said that Womack has a criminal record extending back to 1977, and that he has been arrested for stealing from town libraries.

A letter Womack reportedly sent to the president of the Belmont bank said: "You or your bank will pay me $100,000 or you and your Jew family will be killed."

Womack's phone number is unlisted and he could not be reached for comment at City Jail yesterday.

Richard Baker, the FBI special agent who assisted in the investigation, also could not be reached for comment yesterday.

Investigators said one major lead in the case developed in November at a monthly meeting of area university police officials.

During the meeting, a Northeastern University detective mentioned that police there had experienced several book thefts accompanied by threatening letters.

Harvard police Sgt. Kathleen Stanford, one of the University's most successful investigators, said she recognized similarities to the Widener slashing case.

Since that November meeting, Stanford, Rooney and the three other Harvard detectives assigned to the case worked 12-hour days for two and a half straight weeks.

"This took a tremendous amount of determination," said Rooney, the head of the Harvard police criminal investigations division.

"When I heard from Northeastern about the threatening letters and the connection to Widener Library I thought: "This has to be the guy,'" Rooney said.

Johnson said the routine practice of sharing information with other university police forces was crucial to the ultimate success of the investigation.

"It was this system of networking, of exchanging information, which did it," Johnson said.