Bosses at Chessington Zoo yesterday blasted newspaper reports saying they have not been properly caring for their 10 gorillas.

According to reports in national newspapers the zoo risked seeing its gorilla enclosure closed down if conditions there did not improve.

The information came to light after a Freedom of Information Act request from The Independent.

The newspaper managed to get hold of two unpublished reports one from 2005 and a second from December 2006 expressing grave concern over the condition of the zoo's western lowlands gorillas.

According to the Evening Standard the zoo was criticised in the report for housing the animals in a cage with just a concrete backdrop and a hay floor and a few ropes for swings.

Its successful breeding problem was also cited as making the problem worse causing overcrowding the compound.

However, the zoo hit back arguing the reports were out of date and did not reflect more recent changes and improvements.

A spokesman said: "Chessington took the 2005 Zoo Licensing report extremely seriously and have reviewed and addressed the issues raised. An article based on outdated information does not reflect changes and improvements that have been made and subsequently approved and commended by inspectors.

"Chessington has one of the most successful western lowland gorilla groups in Europe, with 10 gorillas - most of whom were born at Chessington. The successful breeding of gorillas is a testament to the keepers who look after them, and the gorilla group is thriving to such an extent that the European stud book keeper, who visited early 2007, has readily agreed to a new male from another zoo being introduced to the group - something which would not have happened if the facilities been inadequate."