Troops deployed to quell trouble on the streets of Amara on Saturday as the uneasy balance of power between Iraq's security forces and Shia militias threatened to collapse into more violence.
Government negotiators managed to broker a cease-fire in this southern city, restoring order after two days of bloodshed, but more clashes erupted further north as informal gangs of gunmen tested the government's resolve.
"The Iraqi army is on the main streets and intersections," said Shirwan al-Waili, Iraq's minister of state for national security, who rushed to Amara on Friday on the orders of Prime Minister Nuri al-Maliki.
"The police are back in their barracks and there are no militia on the streets," he told reporters in the city.
The medical director of Amara's health department, Zamil al-Oreibi, told AFP that a total of 24 people had been killed in the fighting and 150 wounded, a mixture of police, militia and civilian bystanders.
Armed militiamen left the streets overnight on Friday, troops deployed in numbers and life slowly began to return to normal in this overwhelmingly Shia city of around 350,000 people.
British military spokesman Major Charlie Burbridge said 2,300 Iraqi army troops had deployed in Amara, with 700 more waiting just outside town, and confirmed that the police had returned to barracks.
"The situation is definitely calm, but it's very tense. We suspect that there is a capacity for it to brew up again without any warning," he said.
Clashes erupted on Thursday after police arrested a member of radical cleric Moqtada al-Sadr's Mahdi Army and accused him of planting a bomb which killed a senior intelligence officer.
Relations had been tense between the militia and the police force, which is widely understood to be infiltrated by supporters of a rival Shia movement.
Some 200 to 300 Mahdi Army fighters attacked and burned two police stations and besieged the force's local headquarters, triggering street battles between police and militants armed with assault rifles and rocket launchers.
The Iraqi army sent reinforcements to the town and British forces, which have overall security responsibility in southern Iraq, put a 600-strong battle group on standby to intervene.
Interior Minister Jawad al-Bolani met with Sadr on Saturday in the Shia holy city of Najaf and afterwards praised him for helping to bring the battle to an end.
"There were some regrettable events and now the situation has changed and is under control," he told reporters.
"Moqtada al-Sadr sought to calm the situation and give the security institutions time to play its role," said the interior minister, adding that legal measures would be taken and investigations carried out.
The government may have won only temporary reprieve, however.
Police Lieutenant Colonel Mohammed Hassan told AFP that gunbattles were underway in the town of Suweira, a mainly Shia community on the Tigris river 60 kilometres (35 miles) south-east of Baghdad.
"Two Mahdi Army and one civilian have been killed. Five others are injured: three gunmen and two civilians," he said, adding that two militia vehicles had been burnt in the fighting.
Police in Hilla said they intervened to halt a clash between rival Shia militias after the Mahdi Army was accused of planting a bomb by an office of the Supreme Council for the Islamic Revolution in Iraq (SCIRI).
One SCIRI guard was injured in the blast, police said in Hilla, another mainly Shia town south of Baghdad.