The UK's second oldest oak tree is being protected by mounted police in north London.

The oak, which scientists believe is more than 450 years old, stands in the 250-acre Bentley Priory Open Space in Stanmore - a site of Special Scientific Interest and home to extremely rare yellow meadow ants and hundreds of species of birds.

But recently gangs of youths have been creating havoc at the reserve, using drugs, causing damage with graffitti and creating noise nuisance.

Stanmore Park Safer Neighbourhoods Sergeant Suzy Rosser came up with the idea that using mounted police would be a good way to deter young hoodlums from being a menace.

Tony Raymond, a local resident and chairman of the Stanmore Society said: "The Stanmore Park Team have had a great impact on the community.

"Seeing police officers patrolling is great and we certainly get the impression that everything is improving.

"This site is unique and I am very pleased that this action has been taken."