German authorities announced that an officer shot a gorilla dead who could not otherwise be euthanized, following the New Year's Eve fire at the Krefeld zoo in North Rhine-Westphalia.

A statement issued by the interior ministry of the state said rescuers searching through the burnt remains of the primate house found a gorilla and a female orangutan still alive in the rubble.

"Our colleagues were obliged to kill the animal by shooting it," read a statement issued by the Krefeld Zoo. "Otherwise, it (allowing the gorilla to suffer) could be punishable under the Animal Welfare Act."

Read more: German apes likely traumatized after animal deaths in Krefeld Zoo fire

Veterinarians were able to euthanize the orangutan, but had trouble doing so with the gorilla, so a police officer received formal permission to kill it with shots from his submachine gun. "The fastest way to relieve the animal was with a bullet," according to the statement.

Read more: A community mourns as Krefeld Zoo reopens after New Year's fire

The blaze at the zoo killed over 30 animals. Investigators believe the fire was caused by airborne lanterns released by three women celebrating the new year. The lanterns, which are illegal in Germany, landed on the monkey house, subsequently lighting it on fire. The suspects are being investigated for committing "arson with negligence."

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lc/rt (dpa, AP)