OSAKA -- The Osaka District Court found a homeless man not guilty of manslaughter Thursday in the 1995 drowning of an older homeless man, even though the defendant had at one time admitted to throwing the victim into the river.

Judge Takashi Oyama doubted the credibility of testimony by four eyewitnesses as the reason for acquitting Kenjiro Tanabe, 28. "Their testimony varied during the course of the trial," Oyama said.

Tanabe admitted to police before the start of his trial that he threw Akio Fujimoto, 63, into the Dotonbori river in Osaka's Minami commercial district. But he later pleaded innocent in court, claiming he was only nearby and had not touched Fujimoto.

Prosecutors had demanded a six-year prison term, arguing that Tanabe conspired with a friend, Hironobu Sakamoto, to throw the victim, who was sleeping near the Ebisu Bridge, into the river 5 meters below, where he subsequently drowned.

Sakamoto, 27, who testified that he had acted alone when throwing the victim into the river, is appealing a six-year prison sentence.

Oyama upheld Sakamoto's testimony, noting Tanabe's confession had been vague and had not included key details. "There is no proof of the defendant's guilt," Oyama said.

Tanabe and Sakamoto tried to rescue the man after he was thrown in, police said.