A bomber strapped with explosives has killed at least 11 people waiting outside a police recruiting centre for special forces in Iraq's capital, an Interior Ministry spokesman said.

Police commandos and 10 newly appointed police officers were starting their shifts at 9.45am (Baghdad local time) on Saturday when the explosion took place, Walid Khalid, an Iraqi journalist, told Aljazeera.

The bomber was dressed in the police commandos' uniform, and was easily able to enter the headquarters, Khalid said.

"A terrorist reportedly walked into the crowd and detonated his vest, which was packed with ball bearings," according to a military statement.

Medical sources at al-Yarmuk hospital confirmed to Khalid that 11 police officers were killed and 23 others, including some of the new officers, were wounded.

The toll resulting from the explosion may rise as some of the injured were seriously wounded, Khalid reported.

Differing figures

There were conflicting reports on the death toll. A senior Interior Ministry source said 20 people had been killed. Local police and hospital officials reported 17 dead and 21 wounded, while the US military said at least 12 were killed.

Doctors at al-Yarmuk hospital said they were also treating 21 wounded, many of them in serious condition. Others may have been treated elsewhere and some bodies may have been collected by families at the scene.

Explosives

The Interior Ministry source said the bomber wore an explosive vest beneath civilian clothes when he approached the Interior Ministry's Special Forces recruitment centre in the Mansour district of western Baghdad.

Bombers have targeted the recruitment centre, near the Green Zone government and diplomatic compound, several times in the past.

An Interior Ministry source said recruits had been told to come on Saturday, normally a non-working day, in an effort to protect the volunteers.

Cleric mourned

In a Shia Muslim neighbourhood across town, thousands of men held aloft the green-shrouded coffin of cleric Kamal al-Din al-Ghoureify, gunned down near his mosque as he drove to prayers on Friday.

Al-Ghoureify was a Baghdad representative for Ayat Allah Ali al -Sistani, recognised as spiritual leader by much of Iraq's Shia majority.

Mourners crowded the streets chanting and beating their chests.

"It is a calamity for the neighbourhood, for Baghdad, for Muslims and for Shia," al-Ghoureify's weeping brother Abu Hussein said. "What was his guilt? He was an old man, 70 years old and paralysed. What did he do?"

Al-Ghoureify's murder was one of three attacks on prominent Shia targets within 24 hours.

Police officer killed

On Saturday, armed men killed a police officer during an ambush in the northern Iraqi city of Mosul.

Lieutenant-Colonel Anwar Sheikh Kabeer Sorchyee was shot as he was driving to work in the city's northeastern district, police said.

The identities of the attackers were unknown, but anti-US fighters have been active in Mosul - the country's third-largest city - and have targeted senior police and government figures as part of their campaign to drive US troops from Iraq.

PHOTO CAPTION

An Iraqi policeman tries to explain to a U.S. soldier what has happened at the site of a suicide car bomb attack at a checkpoint outside the offices of Iraqi Prime Minister Ibrahim al-Jaafari's Islamic Dawa Party on Friday, July 1, 2005, in Baghdad, Iraq. (AP)