BAGHDAD, Jan 15 (Reuters) - The first additional American troops who will take part in a major new security plan in Baghdad have arrived in the Iraqi capital, the U.S. commander in Iraq, General George Casey, said on Monday. "The initial elements of the first group are here," he told a news conference. He declined to give more details or say when operations would start but he said a report that 4,000 of the planned 17,500 extra troops had arrived was "real high".
