A mechanical excavator detonated what appeared to be an unexploded World War II bomb hidden under the earth in Germany on Friday, killing the driver and injuring 13 other people at a building site, police said according to dpa. Two of those injured were seriously hurt as a result of the explosion, which took place in the western town of Euskirchen near the city of Bonn. Though the bomb disposal team responsible for the blast said it was not yet convinced that the incident had been caused by a wartime bomb, experts said that the device was likely a blockbuster bomb used by the Allied Forces.