"Seven people were killed, two of them children, and 47 injured, including two women. The other 35 were men," said a spokesman for the health ministry.

A US soldier and a civilian security guard were also wounded when another mortar fell between the convention centre, where a key national conference began its last day, and the interim Iraqi government building, the military said.

An interior ministry spokesman said at least one mortar hit a business district in central Baghdad, near the Bab al-Muadaam police station, on the opposite side of the Tigris river.

"At first we thought it was a car bomb, because one building was very badly damaged, but ballistic experts have concluded it was a mortar bomb," said Colonel Adnan Abdul Rahman.

Witness Saadi Shawi, 45, said there were casualties after mortar rounds hit dress-making workshops and damaged cars behind the Hader Khana mosque near Rashid street at around 11:25 am (0725).

Meanwhile, a senior Iraqi police officer was killed late Monday in the flashpoint city of Ramadi, west of Baghdad, but Sunni Muslim militants denied any responsibility in his murder.

Deputy Ramadi police chief Iyad Kharadan was killed at around 9:30 pm (1730 GMT) when attackers rammed his car, killing him before he could escape, said police Captain Salah al-Dulaimi.

The Iraqi national guard commander in the Sunni Muslim insurgent hotspot of Samarra was gunned down with a senior aide Monday in an operation claimed by an underground militant group.

Lieutenant Colonel Ihsan al-Saji and Captain Saddam Hussein were killed on the main highway north of Baghdad as they travelled to the capital, an interior ministry official said.

Saji had already seen one brother killed and another deprived of a leg in reprisal attacks by the insurgents, the official said.

Reuters photographer shot

An Iraqi photographer working for London-based news agency Reuters was shot in both legs Tuesday during fighting between Shiite Muslim militia and US forces in the holy city of Najaf.

Ali Abu al-Shish, 25, was photographing US tanks in the 1920 Revolution Square when fighters loyal to firebrand cleric Moqtada Sadr opened fire on US positions at around 10:30 am (0630 GMT).

"I was hit in the legs as I tried to escape," he told AFP at his hotel after returning from hospital with his legs bandaged.

Jordanian hostage released

A Jordanian car dealer who was kidnapped in Iraq eight days ago was rescued overnight by Iraqi police outside the central holy city of Karbala, he said yesterday.

"Five people kidnapped me in Baghdad eight days ago and took me to this village. They asked me to call my family and ask for 170,000 dollars ransom," Samer Tumallah Hussein Tumallah, 35, told AFP.