A British private security contractor was arrested by Iraqi authorities in Baghdad’s protected Green Zone on Sunday, accused of fatally shooting two colleagues, according to Iraqi officials.

The gunman, identified as Danny Fitzsimmons, was also said to have shot an Iraqi as he allegedly tried to flee the compound, according to Iraqi officials and two other sources familiar with the incident. The Iraqi man was critically wounded, said Maj Gen Abdul Karim Khalaf, a spokesman at Iraq’s interior ministry.