The child remained in a critical but stable condition at a hospital in Cambridge following the incident at Johnsons of Old Hurst, a privately owned zoo in Cambridgeshire, police said.

Authorities had detained a man from Norfolk on suspicion of attempted murder after emergency services responded to reports of a seriously injured child at the zoo. Police later said the suspect had been assessed as not fit for interview and was released on bail until Sept. 18 while investigations continue.

Investigators have not disclosed how the boy sustained his injuries and said they did not believe the suspect and the child were known to each other.

According to police, zoo staff pulled the child from the crocodile enclosure and administered emergency medical treatment before he was transported to hospital.

“Our thoughts remain with the boy and his family and specialist officers continue to support them through this difficult time,” Detective Inspector Verity McCann said in a statement.

Johnsons of Old Hurst said it had temporarily closed its Tropical House section out of respect for the child’s family, while the remainder of the zoo continued operating.

British media reported that the wife of the zoo’s owner entered the enclosure and helped rescue the child, although police have not publicly commented on those reports.

The facility, which also includes a farm shop, butcher’s shop, tea room and steakhouse, houses more than 100 animals, including lions, tigers, sloth bears, capybaras, meerkats and crocodiles, according to information published on its website.

Police said inquiries into the circumstances surrounding the incident remain ongoing.