An Egyptian accused of being a mastermind of the Madrid train bombings denied Monday that his voice is the one heard in a wiretapped telephone conversation in which prosecutors say he claimed the attacks were his idea. "That voice is not mine. I'm not the person speaking," Rabei Osman said of the recordings as he took the stand for the second time in the trial over the March 2004 attacks, which killed 191 people and wounded more than 1,800. Italian police arrested Osman in Milan, Italy, in June 2004, acting on a tip from their Spanish counterparts. Italian prosecutors say that in a series of wiretapped conversations Osman tells an associate in Italy, "I'm the thread to Madrid; it's my work." Osman told the three-panel judge overseeing the trial that the official translations of those Arabic-language conversations were inaccurate. He said there is no mention of anyone claiming the Madrid attack at any moment of the discussion between two men heard in the conversations.