BAGHDAD — With not a Shiite fighter in sight, shoppers crowded through markets and cars packed the streets in Baghdad’s Sadr City yesterday — a positive early sign for Iraqi forces in their bid to impose control following a truce with the militia in its stronghold

But while peace held in the sprawling slum a day after thousands of Iraqi troops rolled in, there were indications that militants were increasing their activity elsewhere. Skirmishes broke out in some nearby districts, including a clash that the U.S. military said killed 11 Shiite gunmen

Support for the anti-U.S. Shiite cleric Moqtada al-Sadr is high among Sadr City’s 2.5 million residents, nearly half the population of Baghdad. Many see his Mahdi Army fighters as their protectors against Sunni insurgents and the distrusted American forces

Yesterday, however, people seemed relieved by the deployment and the calm it brought after weeks of clashes between his Mahdi Army fighters and allied American and Iraqi troops on the edges of the district and in its southern sector

A day laborer, Alaa Jassem, said the Iraqi troops were welcome — “they are our brothers, our sons, our friends” — but said the government “must be sincere in its promises and deliver aid to the city.” The Iraqi government has said that as part of the deployment, it will direct funds for reconstruction in Sadr City, which is plagued by poor sewage systems that often overflow, drinking water shortages, and poor garbage collection

Success in Sadr City would be a major boost to Prime Minister al-Maliki, whose government is seeking to show it can extend its authority over parts of the country long under the control of armed groups

Much depends on the durability of a truce reached last week between the government and the Mahdi Army. None of the black-garbed fighters was seen on the streets yesterday, and Sadrist Movement officials say they will stick by the cease-fire. But some have already complained about the unexpected size of the deployment, saying it could provoke the fighters, who still have their weapons

Ten thousand Iraqi soldiers and police, backed with tanks, moved into Sadr City early Tuesday in the biggest government effort yet to impose control in the bastion of the Mahdi Army

Yesterday, Iraqi forces sought to solidify their hold on the district

The troops assumed a high profile in the streets but appeared to be working delicately to avoid provocations

Soldiers set up more positions and patrols on the main avenues, sometimes stopping their vehicles to establish a temporary checkpoint — but searches of passers-by were rare. One checkpoint stood near the main office the Sadrist Movement, and a tank was positioned in a nearby square

On Gayara Street, a main avenue running the length of Sadr City, cars, motorcycles, and minibuses were jammed — a stark contrast from recent weeks — and soldiers joined police in directing traffic. Some residents brought water for soldiers, and a nearby market was bustling, with sellers announcing their prices on loudspeakers.