Baghdad, Iraq ? A Shiite alliance won a slim majority in Iraq’s new National Assembly, according to certified election returns announced Thursday, but it may take weeks to form a government. Meanwhile, interim Prime Minister Ayad Allawi cautioned against excluding all of Saddam Hussein’s supporters.

Because a two-thirds majority in the 275-member parliament is required for confirming the top positions in the new government, the United Iraqi Alliance will have to make deals. The alliance won 140 seats, while Kurdish parties got 75, secular Shiites took 40 and nine smaller parties shared 20, according to final returns of the Jan. 30 elections.

Shiite and Kurdish leaders already have agreed they must reach out to prominent Sunnis to participate in the government if they want it to be considered legitimate among Sunnis and to have any hope of ending the country’s largely Sunni-led insurgency.

The Sunni-led Iraqis Party won only five seats in parliament, because many Sunni Arabs avoided the elections — out of fear of violence or to support a boycott call by clerics opposed to the U.S. military.

Allawi said the alliance must change its platform of purging Sunnis who were members of Saddam’s Baath Party from government positions if it wants national unity.

“The alliance talks about de-Baathification. I hope if they get control and they’re chosen to be the ones running the country, I sincerely hope that they revisit these issues in their program and re-discuss it with a view of having reconciliation and national unity,” Allawi said.

A woman and children walk past a sign in support of Shiite cleric and politician Abdel-Aziz al-Hakim in Karbala, Iraq. Iraq's electoral commission certified the results of the country's Jan. 30 elections Thursday and allocated 140 seats to the clergy-backed United Iraqi Alliance, giving it a majority in the new parliament.

The key challenge for the new government will be ending the insurgency that kills dozens of people every week. Most Iraqis say only negotiations will end the attacks.

In Baqouba, 35 miles northeast of Baghdad, Iraqi police killed two men with suspected links to al-Qaida’s affiliate in Iraq and arrested five others during raids, the city’s police chief, Major Gen. Adel Molan, said Thursday.

“We found huge amounts of weapons, including mortars, assault rifles and explosives. We also found computers and CDs which show the beheading of several hostages in addition to letters which they were about to send to Osama bin Laden,” Molan said.