MI5 are opening a new regional office to cover West Yorkshire in the wake of the London attacks.

The agency is also to increase manpower by more than 50% to 3,000 to combat extremist recruits like Germaine Lindsay, from Rawthorpe, and Mohammed Sidique Khan, of Dewsbury.

The pair, who killed more than 30 people between them in the London attacks, were known to security forces both in the UK and the US. Fatally neither were tracked.

MI5 want to stop any repeats of the July 7 attacks and are aiming to get the new bases and officers working by the end of 2008.

An intelligence source said: "This regional growth forms part of the expansion of the service announced by the Home Secretary. It is in order to increase international counter terrorism work."

Huddersfield MP Barry Sheerman said he welcomed the moves and hoped it would make the security services more accessible to the public.

"It is a great idea to have regional offices, so if anybody thinks anything suspicious is going on they can make someone aware and it can be examined immediately," he said. "I fully support any extra spending on the security services because it will make people safer and stop terrorism.

"People have started to ask questions of the security services as to why the London attacks happened. That is unfair.

"They have worked hard and foiled numerous plots in the past, but it is the nature of security services that when they are successful we do not hear about them."

Other regional offices are to open in Wales, Scotland, the South East and the Midlands.