Police on Sunday searched the home of a man who runs a bear farm in Kazuno, Akita Prefecture, where two female employees were fatally mauled by six of the animals last week.
At the residence of the 68-year-old man, who lives in Odate, investigators said they confiscated management documents regarding the Hachimantai Bear Farm and are investigating him on suspicion of professional negligence resulting in death.
Earlier in the day, police examined the bodies of the six bears, which had escaped and were shot to death after the maulings.
The women died Friday after being attacked off the farm's grounds. The bears are believed to have escaped by climbing up a snowbank in the corner of their playground and scaling the concrete wall surrounding it.
Officials of the Akita Prefectural Government, which oversees the facility, told reporters Sunday that the man was instructed not to let the bears out while the playground was covered in snow. The man said he would comply, they said.
The man, who has been managing the bear farm since 2008, was also repeatedly urged to improve his operations after failing to keep proper documentation, including records for the bears at the facility, they said.
The bear farm was scheduled to reopen later this month after closing for the winter in late October.