Police in northern Japan say a group of bears that escaped from their enclosure at a park have killed two people.

Police said Friday that two female employees in their 60s and 70s at the park near Kazuno City in Akita prefecture were believed to have been feeding the bears from outside the concrete fence before they escaped. Their mangled bodies were found hours after a colleague escaped and called for help.

Hunters later shot and killed all six escaped bears.

Police believe the bears climbed over the fence by climbing onto high-piled snowdrifts. They are investigating the case as possible professional negligence causing death. The privately owned park owns 32 other bears.