The UK’s Royal Navy is set to protect the 2012 Olympics from a 9/11-style attack by placing world’s most advanced destroyer in the Thames estuary.

Security chiefs are planning to tie up one of the navy’s new Daring Class of Type 45 destroyers which has a sophisticated anti-air missile system in the Thames estuary.

The destroyer would shoot down hijacked aircraft and jets flown towards London or the Olympic site by terrorists.

Dauntless, Daring and Diamond are three Type 45 destroyers those are built at an estimated cost of £1bn each and will be ready for service by 2011.

The Type 45 destroyer will provide instant radar coverage of up to 250 miles.

The anti-air missile system is the main weaponry to the Royal Navy which defends against supersonic, stealthy, highly manoeuvrable missiles that could use steep-diving flight profiles approaching in salvos, simultaneously from several directions.

Experts stated that its 45 super-agile Aster missiles are capable to track and destroy a moving target of a cricket ball size at 19 miles.

The ship provides a secure, independent radio net linked to a military satellite, according to a senior Scotland Yard source.

This naval operation will add additional costs to the £600m security budget for the Games.