TWO suspected terrorists were arrested at gunpoint in front of shocked Blackburn residents as the "War on Terror" hit East Lancashire.

Armed Metropolitan Police officers swooped in Preston Old Road, Cherry Tree, at around 3.30pm yesterday as part of a nationwide operation.

Eleven others were arrested in London, Hertfordshire and Bedfordshire. Police sources today confirmed at least one of those arrested was from Blackburn.

A terrace house in Shakeshaft Street, Audley, Lower Audley Tyre Centre, Bennington Street, and houses in Greenhead Avenue, Little Harwood, and Whalley New Road, were searched by officers at 9.30pm.

The Met revealed properties across the country were being combed for explosives.

Scotland Yard has refused to reveal whether the raids, believed to be co-ordinated with MI5, were linked to the seizure of computer files from al Qaida suspects captured in Pakistan.

The 13 suspects, all in their 20s and 30s, were taken overnight to the secure Paddington Green police station in central London and were being interviewed today. Police have the power to hold them for 14 days.

Eye-witnesses described how two police cars blocked in a gold, H-registered Mercedes in Cherry Tree.

Passers-by were bundled into shops and residents ordered to stay indoors as undercover officers surrounded the car.

People described two Asian men being pulled out and forced to the floor at gunpoint, before being dressed in white plastic clothing and taken away in another unmarked car.

A 100-metre length of Preston New Road - one of the main routes into Blackburn - between Green Lane and Cecilia Road was cordoned off for nearly two hours.

A man who said he was related to the owner of the house in Audley, said: "My uncle owns the house but he is in Pakistan at the moment.

"There have been forensic officers in there and we have been told they are looking for explosives but they have been given the wrong information."

A police officer remained on duty outside the address today.

The arrests came as Prime Minister Tony Blair came under pressure to spell out the level of the terrorism threat in Britain, as a massive security operation continued in US cities. Foreign Secretary and Blackburn MP Jack Straw is currently on holiday. Chief Superintendent David Mallaby, commander of the Eastern Division covering Blackburn, had spent the day in London but flew back to East Lancashire late last night following the arrests.

He said: "There is nothing local people should be worried about. All sections of the community are against terrorism and want a peaceful life.

"They are extremists from all walks of life and we must remember the people arrested are suspects and none have been convicted of anything.

"Local officers have been involved in a large number of aspects of the operation but have only been given information they need to know."

After the plain-clothed, armed officers left Cherry Tree, local officers took over, directing Traffic away while they waiting for a recovery vehicle to take the Mercedes away.

Traffic backed up in both directions, with local bus companies forced to cancel some services.

Jayne Winward, 32, watched events unfold from the bedroom of her home with 23-month-old son, Joe.

She said: "The first I heard was some shouting and I went to the front to see what was going on.

"I saw people running around so I went to the front door. A policeman told me to get back indoors.

"One man was pulled out of the car, and made to kneel on

the floor with guns pointing at his head.

"They put plastic on his feet and arms and then made him put this white plastic suit on. They did the same to the other man, who was on the floor.

"All the time, two unmarked cars were blocking the road. The officers were going backwards and forwards.

"The two men were taken away in a different car. It's the sort of thing you never imagine happening in your own street."

Resident Pearl Bernasconi said she was alerted to the police activity by the build-up of traffic outside her home.

The grandmother said the road was closed for more than two hours and she saw armed police, forensic experts, and two cars speed up to a cordon.

She added: "They must have been official cars because shortly after they drove off at speed with forensic men and my granddaughter seemed to think two men - one in each of the cars - were wrapped in silver foil in the middle of the back seat."

The white plastic suits have prompted speculation that dangerous chemicals were involved in the operation. However police have refused to comment on this.

Eye witnesses at the Lower Audley Tyre Centre, off Bennington Street in Audley, said police arrived in vans at the lock-up last night.

Members of the Asian community gathered outside the building this morning. One man, who described himself as a prominent member of the town's Kashmiri Association, said: "This is very worrying. Something has to come from it or it could damage race relations in Blackburn. Until anything is fact there will be a lot of rumours."

Coun Hussain Akhtar, also visited the site. He said he was mystified about what was going on and described it as "worrying".

Police stressed the Lower Audley MOT Centre, which shares the same unit as the Lower Audley Tyre Centre, was not subject to any police searches and was trading as normal.

A spokesman for the Met said he could not say whether those arrested were British citizens and added: "Thirteen men were arrested under the Terrorism Act 2000 as part of a pre-planned, on-going intelligence-led operation. The men have been arrested on suspicion of being concerned in the commission, preparation or instigation of acts of terrorism.

"The operation is part of continuing and extensive inquiries by police and the Security Service into alleged international terrorism."

Bus services only began to get back to normal after 5.30pm yesterday.

Terry McGaghey, duty manager at Lancashire United said: "All our drivers were radioing in saying they were being diverted.

"It caused us chaos."

And a spokesman for StageCoach in Chorley said they had also been diverted.

He said: "One of our drivers rang up saying there was a problem and we have had to re-route."