Campaigners who want to stop Olympic equestrian events being staged in Greenwich Park have threatened to use a legal loophole from the 19th Century.

They said organisers for London's 2012 Games will be breaking a law from 1866 if they seal off parts of south east London's Blackheath.

Residents group No to Greenwich Olympic Equestrian Events (Nogoe) has raised fears the venue will cause permanent damage to the Blackheath.

But the London Organising Committee for the Olympic Games said trees would not be cut down for the arena.