An Iraqi reporter working for the New York Timeswas shot dead on his way to work in Baghdad on today, the newspaper said.
The killing of Khalid Hassan (23), came a day after a photographer and driver working for Reuters were killed in the city in what witnesses said was a US helicopter attack but which the military described as a firefight with insurgents.
Mr Hassan was shot dead in the Saidiya district of the capital, the Timessaid in a statement. The circumstances of the attack were unclear, it said.
"Khalid ... was a resourceful and brave member of our news team, who met the many professional and personal challenges of his four years on our staff with enduring good humour and optimism," said John Burns, the paper's Baghdad bureau chief.
Iraqi police have blamed American military action for the deaths of Reuters photographer Namir Noor-Eldeen (22) and driver Saeed Chmagh (40).
The U.S. military said the pair died after a clash between its troops and insurgents yesterday. The incident was under investigation, it has said.
Iraq is the world's most dangerous place to report. At least 149 journalists and media assistants have been killed in the country doing their jobs since the 2003 US-led invasion, according to a count kept by New York advocacy group the Committee to Protect Journalists.
The vast majority have been Iraqis.
Earlier today, gunmen killed five Iraqi government guards outside the ministry of the interior in central Baghdad. Police said nine other guards were wounded in the early morning machinegun attack on a watchtower at the main gate of the ministry's compound.
US and Iraqi forces are engaged in a security clampdown to thwart attacks in the capital and disrupt massive bombings that have inflamed sectarian tension between minority Sunni and majority Shia Arabs.