BALTIMORE (AP) _ A convicted killer who fled a Tennessee prison 12 years ago hanged himself after being captured here by FBI agents, officials said.

Ralph Canady, 43, was serving a 99-year term for the killing of two Nashville, Tenn., policemen when he escaped in 1974 with two other inmates, said FBI spokesman Andrew Manning.

Manning said Canady lived in the Baltimore area for the past several years under an assumed name and was working for a janitorial service.

Canady gave a different false name when he was arrested recently on a minor drug charge. He was released after that arrest, but a subsequent check of his fingerprints revealed his identity, and the FBI was able to find him through the registration of the car he was driving when arrested.

He was arrested again Tuesday in Cockeysville, Manning said. He said Canady was found hanging in his cell early Wednesday.

The other two escapees, also serving 99-year terms in the case, remain at large, Manning said.

A fourth man, Charles Lee Herron, 48, was charged in the 1968 slayings but was never apprehended and has been on the FBI's ''10 Most Wanted'' list since then.