An animal keeper died apparently after being attacked by a lion at a zoo in northeastern Japan, police and the facility's operator said Thursday.

Kenichi Kato, 53, was found bleeding from the neck in the lion cage at Tohoku Safari Park in Nihonmatsu, Fukushima Prefecture, at around 3:25 p.m., the police said, adding he was taken to a hospital in an unresponsive state and later pronounced dead.

The scar suggested Kato had been mauled by an animal, and security camera footage showed a lion pouncing on him, according to the police and the zoo's vice president Norichika Kumakubo.

Kato, an experienced staffer who had worked at the zoo for more than 25 years, was apparently attacked while trying to close the door between the cage and the workers' passage, Kumakubo said.

The zoo said it will be closed until safety management measures are improved.