- Seven men are arrested this week after police find weapons hidden in a car
- The vehicle was stopped by police on suspicion of being uninsured
- Security has been stepped up in Britain ahead of the Olympic Games
London (CNN) -- Seven men have been arrested in the United Kingdom on suspicion of terror offenses, West Midlands police said Friday.
The arrests on Tuesday, Wednesday and Thursday followed the discovery of firearms and offensive weapons hidden in a car stopped by police last weekend who believed it was uninsured, the police said.
The news comes as Britain is in a state of heightened security ahead of the London Olympics, which open in three weeks.
On Thursday, armed police in Staffordshire closed a major highway and called in bomb disposal squads when a passenger on a bus raised the alarm over smoke coming from a fellow traveler's bag. The source turned out to be a quit-smoking aid, and no arrests were made.
Police in London also arrested six people Thursday on suspicion of committing, planning or instigating terror offenses. Those arrests were not related to the Olympic or Paralympic Games, police said.
The arrests announced Friday involve six men from the West Midlands, all in their 20s, and a 43-year-old man from West Yorkshire.
The seven men have been detained on suspicion of the commission, preparation or instigation of acts of terrorism, a police statement said.
Detective Chief Supt. Kenny Bell of the West Midlands Counter Terrorism Unit said: "As soon as the items were discovered in the impounded vehicle, our priority was to protect the public by pursuing and arresting those we believed to be involved."
The weapons are being tested, and police are searching a number of addresses, the statement said.
No information has yet been given on the motivation of the suspects.
Additional security measures will be in place in London and elsewhere during the Olympics.
They include the siting of missile defense systems around the capital and fighter jets on standby at air bases close to London. Police and intelligence agencies have also stepped up monitoring efforts.
Government officials from Washington to London insist there are no known specific or credible terror threats tied to the Olympics. Nonetheless, authorities on both sides of the Atlantic are urging vigilance.
The Metropolitan Police is leading the "largest peacetime operation" seen in the United Kingdom as it seeks to keep the public safe, it said, with up to 9,500 police officers from London and elsewhere to be deployed on the busiest days of the Olympics.
As a result, London's residents and its visitors can expect to see a large police presence on the streets and airport-style security at Olympic venues.
CNN's Laura Perez Maestro contributed to this report.
