A criminal investigation is underway after a missing teenager’s remains were found inside a lion’s enclosure at a Pakistani zoo.
According to CNN, 18-year-old Muhammad Bilal worked as a gardener at Lahore Safari Zoo and was first reported missing on Monday.
On Wednesday, a human skull and two bones were found inside an enclosure at Safari Park Lahore in an area that housed four lions, Chaudhary Shafqat, deputy director of Lahore Safari Zoo, told the outlet.
Fragments of Bilal’s clothing were also found in the enclosure.
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It is unclear how Bilal entered the lion pen, however, Shafqat contended that “the facility was totally safe.”
“There is a safety fence in place, but that is to keep the animals in their enclosures,” he told AFP.
He explained that police are investigating whether the teen went in by choice or if he was thrown over the fence by another person.
This is the first time an incident of this kind has happened at the park, Shafqat added.
A representative from Lahore Safari Zoo did not immediately return PEOPLE’s request for comment.
According to AFP, the police will be reviewing camera footage from the park to determine how the incident happened.