Unidentified men have opened fire on Sunni Muslim worshippers at Friday prayers in two mosques south of Baghdad, killing two people and injuring four, police said.

The first attack occurred when a lone man entered the Mizael Basha mosque in the town of Zubeir, 20km southwest of Baghdad and sprayed automatic fire on worshippers during dawn prayers.

One man was killed and four injured, police Col. Nouri al-Fayadh said.

Another Sunni mosque, the al-Rashidiya, was later attacked by a group of men who fled after shooting dead a guard, police said.

In another incident on Friday morning in the capital, one person was killed and another wounded near a downtown hotel in what appeared to be a bomb attack on a private security convoy, according to an interior ministry official.

There were no immediate details on the identity of the victims.

Two Apache attack helicopters could be seen circling the area.

Convoy targeted

Another bomb was reported to have targeted a US military convoy, witnesses said. There were no reports of casualties in that incident.

Despite initial reports that a blast occurred near the Green Zone that houses Iraqi government offices, and the US and other embassies, a military spokesman said there were no reports of attacks there.

Security in the zone was boosted on Thursday after reports that several bombers were trying to penetrate the area, a frequent target for attacks. 

US soldiers killed

Meanwhile, three US soldiers were killed in clashes in Baghdad and in a city south of the capital.

Two of the victims died on Thursday afternoon in Baghdad after their patrol was struck by a roadside bomb, a US military statement on Friday said. 

The soldiers, who were not identified, were part of Task Force Baghdad.

Another US soldier was shot dead in the city of Iskandariyah in central Iraq on Wednesday, the military statement said.

The death occurred during combat operations near the city located 50km south of Baghdad.

The soldier, who was not identified, was assigned to the 155th Brigade Combat Team, II Marine Expeditionary Force.

PHOTO CAPTION

Mourners pray outside a Sunni mosque next to the casket of Maad Yousif during his funeral in Baghdad, Tuesday, Aug. 23, 2005. Unidentified gunmen abducted the engineer in Azamyaa two days before and his corpse was found Tuesday in the Baghdad morgue, despite his family having paid a 20,000 US dollar ransom. (AP)