BAGHDAD — American-led forces handed over control of a province south of Baghdad to the Iraqi government on Wednesday, reflecting the improvement in security across the country.

While violence continued across the country, with two civilians dying in a car bomb in the northern city of Mosul and 28 people killed in a suicide attack a day earlier, the handover of Qadisiyah marked one more success for Iraq's increasingly assertive government.

Iraqi leaders are now seeking a timeline from the United States for the withdrawal of American forces.

The mostly Shiite region was the 10th of 18 provinces to fall under Iraqi authority after U.S. and Polish forces relinquished control in a ceremony. In a statement, U.S. Ambassador Ryan C. Crocker and Gen. David H. Petraeus, commander of U.S. forces in Iraq, said Iraqi security forces there had been operating "independently" for the last two months.

"We will assist as requested," they said. The statement said the Iraqi provincial and military leadership would have to create long-term security that can lead to economic development.

Qadisiyah had been the scene of fighting among Shiite factions, and U.S. and Iraqi troops launched a major operation there last year. The handover was delayed from last month.

U.S. forces also have pushed back the handover of Anbar province, west of Baghdad, where occasional bombings and combat occur despite a sharp decline in violence. Anbar had been a stronghold of al-Qaida in Iraq and other extremist groups until Sunni tribes turned on them and allied with the United States.

Diyala province, northeast of Baghdad, is another trouble spot. On Tuesday, two suicide bombers killed 28 people in a crowd of army recruits outside a military base there. Iraq has said it will soon launch another offensive in Diyala against the militants there trying to regroup.

U.S. commanders say they will assist in the operation.

Some insurgents are also believed to have holed up in Mosul after being driven out of other urban strongholds, and relatively small-scale attacks happen there on a daily basis. On Wednesday afternoon, a car bomb exploded in the eastern part of the city, killing two people and injuring nine, police said.

About an hour earlier, on the same side of the city, a suicide bomber blew up a car near a U.S. military patrol and six civilians were injured, a police official said. He spoke on condition of anonymity because he is not authorized to speak to the media.

Also Wednesday, the Iraqi Red Crescent Society said its chief and two deputies were summoned by an investigative court in a corruption probe.

Adnan al-Kadhimi, one of the deputies sought for questioning, said Red Crescent chief Saeed Haqi is out of the country on official business and is heading for the United States.

The third official summoned by the court left Iraq last year amid a separate corruption investigation.

The details of the investigation into the Red Crescent were not immediately known, but al-Kadhimi says the agency is preparing a legal defense.

Red Crescent organizations are the Muslim world's equivalent of the Red Cross. In Iraq, the group plays a major role in conducting aid operations throughout the country.