A 30-year-old man has been arrested on suspicion of attempted murder after a three-year-old boy sustained serious injuries after ending up inside a crocodile enclosure at a zoo in eastern England, police said. The incident occurred on Thursday afternoon at Johnsons of Old Hurst, a family-run farm and zoo in Huntingdon, Cambridgeshire. According to the Cambridgeshire Police statement, the child "ended up in the crocodile enclosure" and was rushed to a local hospital. The boy remains in critical but stable condition.Police said the arrested man is believed to be a stranger to the child. "At this stage we are speaking to people who were at the zoo at the time of this distressing incident to understand more about the circumstances," Det. Insp. Verity McCann said in a statement. "We do not believe the man arrested and the child are known to each other."The investigation remains ongoing. Huntingdon Member of Parliament Ben Obese-Jecty expressed support for the victim and his family."My thoughts are with the young victim and his family during a hugely traumatic and difficult time," he said in a statement on facebook."This is now a live criminal investigation and I would ask people to refrain from speculation online," he added.Johnsons of Old Hurst told BBC that its tropical house, which houses several species of crocodiles and other reptiles, will remain closed until further notice "out of respect to the family."