A fire at a zoo in western Germany killed a large number of animals in the early hours of the new year, authorities said.

They did not comment on local media reports that the blaze was started by fireworks.

Krefeld Zoo, near the Dutch border, said the entire ape house burned down and all the animals inside died.

The dpa news agency, quoting officials, said the dead animals included chimpanzees, orangutans and two gorillas, as well as fruit bats and birds.

However, the zoo said on Facebook that the nearby Gorilla Garden escaped the flames and that gorilla Kidogo and his family are alive.

“An unfathomable tragedy hit us shortly after midnight.” the zoo said. “Our ape building burned down to the foundation.”

Both the zoo and city officials said they did not know what had caused the fire and that police are investigating.

They would not confirm local media reports that New Year’s Eve fireworks could have started the blaze.

The zoo remained closed on Wednesday.