BAGHDAD, Iraq (AP) – Seven car bombs exploded across the capital Monday, 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.

Elsewhere, four roadside bombs, six drive-by shootings and a mortar round killed a total of 15 Iraqis in Baghdad and other areas, police said.

The violence underlines the challenges Prime Minister-designate Jawad al-Maliki faces as he begins the tough task of assembling a Cabinet out of Iraq’s Shiite, Sunni and Kurdish parties. Al-Maliki has 30 days from April 22 to present his Cabinet to parliament, but a top Shiite official, Ridha Jawad Taqi, said he expected the lineup to be finalized within 15 days.

On Monday 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.

U.S. Ambassador Zalmay Khalilzad, a key player in protracted political negotiations since Iraq’s Dec. 15 elections, repeated his call for the quick creation of a Cabinet of “competent” ministers _ implying those chosen for their skills and not sectarian or political ties.

The United States is hoping the new government will unify Iraq’s bitterly divided factions behind a program aimed at reining in both the Sunni-led insurgency and the Shiite-Sunni killings that has escalated during months without a stable government.

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, said police Lt. Bila Ali.

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, said police Maj. Abbas Mohammed Selman. U.S. forces closed off the area, and it was not immediately known if there were American casualties.

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, said police Lt. Ali Abass.

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

Police in Abu Ghraib, just outside Baghdad, found a small truck containing the bodies of 15 men who had been tortured in captivity, said police Lt. Maitham Abdul Razzaq. Two other corpses were found in southwest Baghdad; one appeared to have been hanged, said police Capt. Qassim Hassan. Three bodies were found in the northern city of Mosul, including that of a university student who had been kidnapped hours earlier, police said.

On Sunday, at least three U.S. soldiers and 31 Iraqis were killed, including seven who died when mortars hit just outside the heavily guarded Green Zone in Baghdad, not far from Iraq’s Defense Ministry.

Sunni Arabs say Shiite militias have infiltrated the Interior Ministry _ controlled by the biggest Shiite party _ and used death squads to kill Sunnis following the Feb. 22 bombing of a Shiite shrine in Samarra, north of Baghdad. But the killings have gone both ways.

Police said the bodies of six Shiites were found Sunday in the mainly Sunni district of Azamiyah in Baghdad, their hands and legs bound and their bodies showing signs of torture. Two more bodies were found in a mixed district south of Baghdad.

The chief of the Azamiyah district council, Sheik Hassan Sabri Salman, said relatives also identified the bodies of 14 Sunnis kidnapped last week. The bodies were handcuffed with signs of torture, he said. Police did not confirm the deaths.

The Iraqi Islamic Party, the main Sunni faction in parliament and a likely participant in the next Cabinet, warned of “the repercussions of sectarian cleansing.” It urged the new government to stop “the criminal gangs” involved in the killings.

Khalilzad also said Iraq’s next government must decommission sectarian militias and integrate them into the national armed forces, warning that the armed groups represent the “infrastructure for civil war.” He spoke at a news conference with Iraqi President Jalal Talabani in the northern city of Irbil.

A key question will be control of the Interior Ministry, currently held by the Shiite Supreme Council for the Islamic Revolution in Iraq. The SCIRI ran the feared Badr Brigade militia during Saddam Hussein’s rule but insists the group has given up arms, a claim many Sunnis reject.