A Russian shop assistant has been found guilty of 48 murders, which he once said he recorded on a chessboard.
A Moscow jury convicted Alexander Pichushkin, known to the Russian media as the "Bittsa maniac", after four hours of deliberation.
Most of the murders were committed over five years, in the Bittsa Park in Moscow's southern suburbs.
Pichushkin has never denied the charges. He was also found guilty on three counts of attempted murder.
He is due to be sentenced later this week.
The jury found there were no mitigating circumstances, and rejected a defence request to clear him of 18 of the killings. The prosecution has requested a life sentence.
Many Russians would like to see him executed but Russia has suspended the use of the death penalty.
Afraid to go out
Pichushkin began his 14-year killing spree in Moscow in 1992, and was arrested in June 2006.
His victims were drowned in a sewer or bludgeoned to death with a hammer, investigators say.
The BBC's James Rodgers in Moscow says people living near the park where he stalked his victims became afraid to venture out even for a walk.
Pichushkin originally said he planned to carry out 64 killings, one for each square on a chessboard.
But he later denied this, saying he would have carried on killing indefinitely if he had not been arrested. He puts the number of his victims at 61.
Many were elderly men who got drunk with him, investigators say, though he also killed three women.
The vigilance of a relative of one of the dead led to his capture.
Before the Pichushkin case came to light, Russia's most notorious serial killer in recent times was Andrei Chikatilo, who killed 53 women and children in the southern city of Rostov. He was convicted and executed in 1994.