German police had arrested a third man who was allegedly involved in a failed plot to blow up passenger trains, German federal prosecutors said on Friday.

The suspect was detained in Germany's southern city of Constance and his room in a student residence had been searched.

The police did not give the identity of the man, only saying he was a friend of the two suspects who had been arrested earlier on charges of planting bombs on two trains.

Jihad Hamad, a 20-year-old Lebanese student, was detained after turning himself in to the police in Lebanon's northern city of Tripoli.

The first and main suspect, a 21-year-old Lebanese student identified as Youssef Mohamad E.H., was arrested in Germany's northern city of Kiel last weekend.

Both suspects were filmed by security cameras on July 31 in Cologne, each carrying a suitcase aboard trains heading for Dortmund and Koblenz respectively.

The suitcases contained explosives that failed to detonate because of construction errors.

Flammable materials, receipts for gas canisters, wiring and black self-adhesive tape were found in Hamad's apartment in Cologne.

(Xinhua News Agency August 26, 2006)