American shot dead in Baghdad is named as questions remain over motive

Iraqi security forces gather outside a morgue of Sheik Zayed hospital in Baghdad (Hadi Mizban/AP)

An American aid worker shot dead in central Baghdad has been identified as Stephen Edward Troell, the US embassy based in Baghdad said.

Mr Troell, 45, from Tennessee, was killed by unknown attackers as his car pulled up to the street where he lived with his family in the city’s central Karrada district.