A man armed with a knife invaded a facility for disabled people in Sagamihara, south of Tokyo, in the middle of the night on Tuesday morning and stabbed 15 inmates to death and left 45 others wounded. He later turned himself in to police.

Japan’s public broadcaster NHK confirmed that a suspect with family name Uematsu, had been arrested after he attacked residents of the Tsukui Yamayuri En (Tsukui Lily Garden) facility in Sagamihara in Kanagawa Prefecture, south of Tokyo.

The Japanese media said that the staff called police at 2:30am local time with reports of a man armed with a knife on the grounds of the Tsukui Yamayuri Garden facility.

However, one news agency, Kyodo, put the death toll at 19. If confirmed, the knife attack would be one of the worst crimes in Japanese postwar history.

The 45 injured victims were taken to at least six hospitals in the western Tokyo area and Emergency workers said 20 of the injured people were in serious condition.