Brighton city centre is in the grip of the tightest and most high-profile security operation in its history.

The full might of the £3.7 million crackdown was felt yesterday as hundreds of delegates arrived for the start of the Labour conference.

The city was teeming with police officers, many of them carrying guns, as conference security was stepped up in the wake of the July terror attacks on London.

Police vehicles patrolled the streets while a helicopter circled overhead. A semi-rigid coastguard boat patrolled the shoreline.

Security was at its tightest around the secure island site where the conference is taking place. Officers on the roof of the Brighton Centre were scouring the seafront with binoculars and alerting colleagues on the ground of any suspicious characters.

A group of four young Asian-looking men were stopped, quizzed and searched by eight officers.

1,300 police officers will be used during the week-long operation.

Monday, September 26, 2005