A zookeeper was reportedly killed by a tiger at the Piteşti Zoo in Romania.

The man, aged 52, entered the tiger enclosure to clean it on the morning of Monday December 9 and was tragically killed because he did not follow proper safety procedures, according to a newspaper Romanian. Adevărul.

Judicial sources added that the man was killed after the tiger “bit him on the head”, the outlet added, according to a translation from the Romanian original.

According to the zoo’s safety advice, the tiger should have been moved to a highly fenced cage behind a security gate before the man began cleaning its enclosure. However, Adevărul reported that the janitor forgot to lower the security door, allowing the animal to get back in while it was still inside.

“Unfortunately, this deviation led to a fatal attack of the animal,” said a representative of Piteşti City Hall. Adevărul. “Currently, an internal investigation is underway at the zoo to establish the exact circumstances of the incident and any necessary measures to avoid similar tragedies in the future.”

Police confirmed to the British newspaper The Sun that the worker, “did not respect (safety procedures), he forgot to close the safety door, the tiger entered his cage and bit him on the head.”

Meanwhile, witnesses told a Romanian media outlet Zilei Event that this incident was “extremely violent” and that criminal proceedings for manslaughter were opened by the local police, according to a translation from the Romanian original.

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“Investigations are being continued by police officers from the Piteşti Criminal Investigation Bureau in order to establish all the circumstances surrounding the event,” said police from the Arges department, according to the media.

The mayor of Piteşti said it was the first time in 50 years that such an incident had happened, added Zilei event.

“It is an immense loss and our thoughts are with the victim’s family and all their loved ones in these moments of pain,” continued the official.

“It is our responsibility to protect the lives of everyone who works there and also ensure the welfare of the animals.”

“I have ordered the temporary suspension of Zoo activities in order to conduct a thorough investigation,” concluded the mayor. “We will take all necessary measures to avoid further tragedies of this kind.”