A former seasonal worker at Mazda Motor Corp. pleaded guilty Thursday to hitting and injuring eight people with a car at a two-factory complex of the carmaker in Hiroshima Prefecture in 2010 but said he was innocent of the death of a man during the rampage and injuries to two others.

"I acknowledge (guilt) until the eighth person, but not from the ninth, as I don't remember," Toshiaki Hikiji, 44, said at the first session of his lay judge trial at the Hiroshima District Court. He is charged with murder and attempted murder. The dead man was among the 11 people hit by the car he was driving.

Hikiji's counsel argued that while Hikiji may have driven recklessly on the plant premises, he was insane at the time and cannot be held criminally responsible. The Penal Code says acts of insanity are not punishable.