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U.K.: 7 terror arrests over hidden weapons

(CBS/AP) LONDON - Seven men have been arrested on suspicion of terrorist offenses in Britain after a routine vehicle search turned up firearms and weapons, police said Friday.

The arrests took place earlier this week. West Midlands Police said Friday a car was stopped on the M1 motorway in South Yorkshire on June 30 and impounded for not having insurance. It said "firearms, offensive weapons and other material" were later found hidden in it, which prompted police to trace and arrest the driver, passenger and other suspects.

Police said three of the men were arrested Tuesday, three on Wednesday and one on Thursday. Six of them are in their twenties and from the West Midlands area of England, while one is from West Yorkshire.

The men have been arrested on suspicion of preparing or instigating acts of terrorism. They were being questioned by officers and their residences were searched. The items found in the vehicle were undergoing forensic testing.

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The arrests were announced one day after officers in London detained six other terror suspects using stun guns and smoke grenades in an early-morning swoop on a home close to London's Olympic Park.

Authorities have said in both cases that there was nothing to suggest the suspects were to target the Olympics. According to Scotland Yard, Thursday's arrests were part of a long-running investigation that reportedly relate to a plot involving Islamic extremists, reports CBS News' Larry Miller. Those arrested are British nationals.

Britain's terror level is currently ranked as substantial — the third highest point on a five-point scale — and means an attack is a strong possibility.

Intelligence officials say there has been an expected increase in chatter among extremist groups ahead of the Olympics, but there are still no specific or credible threats targeting the Games, which run from July 27 through Aug. 13.

Authorities are consequently responding to potential threats with great assertiveness. On Thursday armed police closed part of the M6 motorway at Weeford after reports of suspicious activity on a bus. A passenger's "smoking bag" turned out to contain an electronic cigarette.

Last week, two Muslim men were arrested - and later released without charge - after they were spotted canoeing on the River Lee, a branch of which runs through the Olympic site.