High Noon at the OK "Green Zone"

The gunman, identified as Danny Fitzsimmons, shot dead a British and an Australian--two employees of the security firm, ArmorGroup-- in the heavily fortified area home to foreign embassies and government offices, the Washington Post reported, citing the Iraqi Interior Ministry.

The paper said Fitzsimmons got into a dispute with his colleagues and then started shooting them.

The gunman also wounded an Iraqi man after shooting him twice in the leg, said Brig. Gen. Qassim Atta, a spokesman for the Iraqi command in Baghdad.

ArmorGroup in a statement confirmed the deaths in a 'firearms incident,' identifying the Briton as Paul McGuigan and the Australian as Darren Hoare.

"We are working closely with the Iraqi authorities to investigate the circumstances of their deaths," said the company's spokesman Patrick Toyne-Sewell.