The tape of the American, broadcast on the Arab TV station Al-Jazeera, showed him identifying himself as Thomas Hamill, 43, from Mississippi. In other footage with no audio, he stood in front of an Iraqi flag, his expression calm but wary as his captors announced their threat on his life. His wife, Kellie, contacted at their home in Macon, Mississippi, confirmed that her husband had been captured. Hamill was snatched on Friday by gunmen who attacked a fuel convoy he was guarding on the main highway on Baghdad’s western edge, the latest in a string of kidnappings in Iraq. Footage released earlier yesterday showed him being whisked away in a car, a gunman in the back seat with him waving an automatic weapon. Insurgents elsewhere in Iraq have seized a Canadian and an Arab from Jerusalem. A British citizen and two German security officials from their country’s embassy in Baghdad are also missing, though it is not known if they have been kidnapped.