Police said Friday they have arrested a man who claimed he sent at least one of a spate of letter bombs at British companies linked to traffic enforcement.

The man was arrested Thursday after he attempted to appear on a radio call-in show, said Assistant Chief Constable Anton Setchell, the national police coordinator for domestic extremism.

The man specifically claimed to have sent a device to Vantis PLC in Wokingham, 40 miles southwest of London. Two employees suffered minor injuries in an explosion there Tuesday.

"At lunchtime yesterday a man claiming to be the Wokingham letter bomber called a national radio phone-in program. He wanted to go on air and claim responsibility and set out his reasons for doing it," Setchell told a news conference.

Instead, a British Broadcasting Corp. employee contacted police, and the 48-year-old man was arrested later in the day.

Setchell said police were investigating whether the suspect was responsible for the attacks. He said the man was being held under the Mental Health Act.

Police have said seven devices have been mailed in the past three weeks, causing minor injuries to eight people.

The three most recent attacks were on offices that have some connection to motorists.

Police said Vantis' clients include Speed Check Services, which provides traffic monitoring technology. On Wednesday, a parcel bomb exploded and injured three women at Britain's driver and vehicle licensing agency.

Two days earlier, a woman was injured by an exploding parcel at the head office of Capita Group PLC, which has a number of government contracts, including setting up and running a system to enforce the $16 congestion charge on vehicles in central London.

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