A three-year-old boy was thrown into a crocodile enclosure by a stranger at a zoo in Cambridgeshire today.

A 30-year-old man from Norfolk, who police do not believe is known to the boy, has been arrested on suspicion of attempted murder. 

The child was rushed to hospital with serious injuries and is believed to be in a 'critical but stable' condition.

Cambridgeshire Police said officers were called to Johnsons of Old Hurst, near Huntingdon, just before 1.30pm today. 

Detective Inspector Verity McCann said: '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.

'We do not believe the man arrested and the child are known to each other.

'Officers are supporting the boy's family at hospital, and our thoughts remain with them.'

Johnsons of Old Hurst is a family-owned zoo with a farm shop, tea room and steakhouse.

It describes itself as 'a working farm and zoo with tropical gardens located in the heart of the countryside'.

The zoo houses more than 100 animals, 'from majestic African lions and Bengal tigers to incredible crocodiles, delightful sloth bears and many more'.

This is a breaking news story. More to follow.