BAGHDAD, Iraq — Seven car bombs exploded across the capital today, killing at least six people and wounding dozens, as politicians met to try to finalize a new Cabinet. Police discovered the bodies of 20 Iraqis — apparent victims of sectarian killings the United States hopes the new government can end.

Three roadside bombs, five drive-by shootings and a mortar round killed 12 Iraqis in Baghdad and elsewhere, police said.

The violence underlines the challenges as prime minister-designate Jawad al-Maliki begins the tough task of assembling a Cabinet out of Iraq's Shiite, Sunni and Kurdish parties.

This morning, political parties met separately in Baghdad to discuss proposed Cabinet ministers and were to meet as a group later in the day, said Kamal al-Saeidi of al-Maliki's Dawa party.

A day earlier, President Bush called al-Maliki, the Iraqi president and the parliament speaker — all named on Saturday — and urged the quick formation of a coalition government. Al-Maliki, a Shiite, has 30 days to choose a Cabinet, but the political parties are under enormous pressure — from Americans and even Shiite religious leaders — to move quickly without the often intractable haggling over ministries.

Baghdad's first car bomb exploded during morning rush hour on a major street near the Tigris River, close to a complex of government buildings, a hospital and a bus station. Three people were killed and 25 wounded.

Two hours later, bombs hidden in two cars parked near Mustansiriya University in eastern Baghdad exploded, killing three civilians, including a 10-year-old boy, and wounding 22 people.

A car bomb also exploded near a square near a U.S. military convoy in central Baghdad, wounding at least 11 civilians, including a young girl.

Bombs in two cars parked about 100 yards apart then exploded one after another near Iraqi police patrols in the New Baghdad part of the capital, wounding three policemen and three civilians.

That was followed by a car bomb that targeted a police patrol in the Mansur area of Baghdad, wounding three policemen and four civilians.