Iraqi cleric Moqtada al-Sadr has demanded that a rival Islamist leader condemn his own followers over deadly Shi'ite Muslim infighting that rocked Najaf.
Clashes broke out on Wednesday night between Sadr's armed followers and a crowd who burned down his offices in Najaf, killing eight people.
That sparked violence in Baghdad and Shi'ite towns across southern Iraq, as members of the pro-Sadr Mehdi Army militia attacked offices of the Supreme Council for the Islamic Revolution (SCIRI) and its 'Badr' militia. SCIRI is headed by Abdul Aziz al-Hakim, a powerful Shi'ite cleric in government.
"I demand that brother Abdul Aziz al-Hakim make an official announcement condemning the aggression by his representatives and some extremists," Sadr told a news conference in the city, where police and troops spread out to keep the peace.
"I call upon the Mehdi Army to be calm because anything else will not be in the Iraqi people's interests," he said, thanking Prime Minister Ibrahim Jaafari for condemning the attack.
Some of his followers were in tears as they inspected Sadr's burnt-out headquarters a short distance from the shrine of Ali, the cousin of Islam's Prophet Mohammed who is revered by Iraq's majority Shi'ite Muslims.
The office saw celebrations earlier this week when it was reopened a year after the Mehdi Army staged an uprising against US forces then controlling the town.
Sadr announced three days mourning over the death of four of his followers and the wounding of 20 in the fighting.
Accounts differed over how Wednesday's violence began. Sadr supporters say a crowd including members of the Badr group stormed the office. Badr movement head Hadi al-Ameri has denied any involvement by the militia, which works with the police.
Witnesses said two rival crowds, one of Sadr supporters and another of Najafi rivals of Sadr, began throwing stones at each other as police stood by.
"What happened made all of us in the city sad. We don't want any more bloodletting in what is supposed to be a city of peace," said shopkeeper Hamoudi Said. Najaf has been spared most of the violence rocking Baghdad and the centre of Iraq where Sunni insurgents are fighting the government and its US backers. But it has not been immune to conflict between Shi'ite factions jockeying for power in the aftermath of the 2003 US-led invasion.
Najaf is home to Sadr, Hakim and his supporters, and Grand Ayatollah Ali al-Sistani, a reclusive figure considered Iraq's most influential Shi'ite cleric. Sadr's powerbase is in the poor Baghdad district known as Sadr City.
Earlier today six Iraqi civilians were killed and 15 wounded when gunmen burst into a popular café north of Baghdad and opened fire.
The attack took place in the small town of Abu Sayda, about 60 kilometres north of the Iraqi capital.
People had gathered at the cafe for breakfast and hot drinks before they were sprayed with gunfire.
It was not immediately clear who was behind the attack, but survivors said they suspected Muslim militants.