Angry unemployed protestors threw stones and lobbed grenades at the public job centre in this south-eastern Iraqi city Saturday, forcing British troops to intervene, police and an AFP correspondent said.
About 500 people gathered outside the building, part of the social security directorate in Amara, 365 kilometers (225 miles) south-east of Baghdad, the sources said.
"The protestors threw stones and sound grenades at the building where police forces had been deployed," Police Captain Shahid Abed Ali al-Tamimi said.
"Windows were shattered," he added.
Tamimi said police forces then withdrew from the building to let British troops take control of the area as coalition helicopters hovered overhead.
One of the protestors, Kazem Hussein Jaber, 24, said the demonstration was meant to demand jobs and denounce cases of "bribes paid to public employees to secure jobs". On January 10, six people were killed and eight others wounded in similar protests in Amara after British forces opened fire on armed men during the demonstration.
Unemployment is a major problem in Iraq, with some putting the jobless rate at 50 percent of the population.
Amara, under British control and populated by the country's Shia Muslim majority, has generally been far quieter than other regions in Iraq, where insurgents have waged a relentless campaign against US-led coalition forces.