MOSCOW, Russia (CNN) -- A Russian serial murderer dubbed the "Chessboard Killer" was given the maximum sentence of life in prison Monday and ordered to undergo psychiatric therapy for a string of at least 48 murders that terrorized Moscow for years.
A Moscow jury convicted Alexander Pichushkin last week of 48 murders and three attempted murders. Pichushkin claimed he had actually committed 60 murders, though prosecutors were unable to find evidence to prove that.
Pichushkin earned the nickname "Chessboard Killer" for saying he had intended to kill one person for each of the 64 squares on a chessboard.
In ordering Pichushkin to receive compulsory psychiatric therapy, the judge said the defendant has a mental disorder but is still sane and cannot avoid responsibility for his crimes.
Throughout his trial, Pichushkin gloated over his crimes and ridiculed the police case against him.
"I was dismayed my work had been attributed to others," Pichushkin said. "In one week, I killed two people. If they hadn't caught me, I would have never stopped. Having caught me, they saved many lives." Watch video report on serial killer Alexander Pichushkin
For years until his arrest in June 2006, Pichushkin kept Moscow on edge, stalking the heavily forested Bitsa Park on the city's southern outskirts and preying on the homeless and elderly. Pichushkin claimed to have committed all but one of his murders in the park.
He lured his victims with the promise of alcohol and, after getting them drunk on vodka, he beat them to death and dumped their bodies in the park. It led Russian media to give Pichushkin his other nickname, the "Bitsa Maniac."
Over the years, Russian police recovered dozens of corpses, some with sticks and vodka bottles rammed into their skulls.
But the crucial lead came in 2005, when a woman Pichushkin worked with at a vegetable store was found dead. She had left a note at her home saying she was going for a walk with him.
Pichushkin said he had been aware of the note but killed her anyway. E-mail to a friend
CNN Correspondent Matthew Chance contributed to this report.