A three-year-old boy critically injured in a zoo enclosure was attacked by a crocodile, the BBC understands.
Cambridgeshire Police said a 30-year-old man arrested on suspicion of attempted murder had been bailed and was "unfit for interview". He reportedly has learning disabilities and had been on a trip to Johnsons of Old Hurst, near Huntingdon, with carers.
It is believed the boy was attacked on Thursday by at least one crocodile after ending up in their enclosure.
He remained in a critical but stable condition. Police said the boy, who was from Cambridgeshire and visiting with his family, sustained serious injuries "while in the enclosure" and was pulled out by zoo staff.
He received medical treatment at the scene before being taken to Addenbrooke's Hospital in Cambridge.
Officers said they were called to the zoo at 13:34 BST on Thursday and were working to establish how long the boy was in the enclosure.