US forces say they have killed 22 militants in renewed violence in Iraq despite a curfew imposed on the capital in response to recent killings.
Baghdad has been under curfew for two days but violence continues
US forces say they killed 10 insurgents in a raid on a bomb-making facility north of Baghdad and 12 in a convoy.
The bodies of 21 Iraqi villagers have been discovered north-east of Baghdad in Diyala province.
President Jalal Talabani has had to postpone a much-anticipated trip to Iran, as Baghdad's airport is closed.
Mr Talabani had been due to meet Iran President Mahmoud Ahmadinejad for talks on Iraq's security situation.
An Iranian news agency is now reporting that he will leave Baghdad on Sunday, provided the airport reopens.
Separately, US Vice-President Dick Cheney has arrived in the Saudi capital, Riyadh, for talks with King Abdullah on the situation in the Middle East, particularly Iraq.
Police in Iraq say gunmen raided the homes of two Shia families, dragged out 21 males and shot them dead.
The bodies were found early on Saturday.
It is thought the youngest victim was a 12-year-old boy.
The attack took place in a village 80km (50 miles) north-east of Baghdad.
The US military says its forces killed 22 insurgents in clashes to the north of Baghdad.
Ten died in a raid on a bomb-making factory in the town of Taji.
A teenage boy was also killed in the crossfire, and a pregnant woman was wounded, US forces say.
The military said it discovered caches of rocket-propelled grenades, machine guns, pipe bombs and anti-aircraft weapons.
It says the weapons were later destroyed in an air strike.
In another incident, US forces said they had killed 12 insurgents in a convoy of cars that ignored warning shots.
One of the dead men was wanted for making car bombs, the military said.
Earlier, Mr Talabani said an all-party conference convened after Thursday's wave of bombings had been a success.
Mr Talabani said delegates at the security conference had agreed to increase co-operation and to "really" participate in the government of national unity.
"For the first time we exchanged frank opinions," he said.
"All parties agreed on the importance of working together and really participating in [Prime Minister] Nouri Maliki's government of national unity."
At least 230 people were killed in two days of violence in Baghdad.
The White House condemned Thursday's bombings and the subsequent retaliatory attacks.
President Talabani said delegates agreed to support the government
"It is an outrage that these terrorists are targeting innocents in a brazen effort to topple a democratically elected government. These killers will not succeed," White House spokesman Scott Stanzel said.
Gunmen attacked Hurriyah, a Sunni Arab area of Baghdad, burning mosques and homes, with at least 30 people reported killed, according to police officials.
The attacks were in apparent revenge for Thursday's bombings that killed more than 200 people in the Shia Sadr City district of the Iraqi capital.
Clashes also erupted in Sadr City on Friday, where residents said a US helicopter fired on militiamen who were launching rocket attacks.
Violence was also reported in other parts of Baghdad and elsewhere in Iraq, including in the northern town of Talafar where a suspected double suicide bombing killed at least 22 people.
There is a real feeling that the situation is moving to the brink amid the cycle of attacks, says the BBC's David Loyn in Baghdad.
To add to the Iraqi government's woes, a key Shia group loyal to cleric Moqtada al-Sadr threatened to quit parliament and the cabinet if the prime minister goes ahead with a planned meeting with US President George Bush next week.
The withdrawal of the group headed by Mr Sadr would deal a major blow to an already unstable government.
In a sermon on Friday, the young cleric appealed for Muslim unity, but also demanded that the leading religious figure from the Sunni minority issue a fatwa against al-Qaeda members.
Moqtada al-Sadr's Mehdi Army militia dominates the sprawling Sadr City slum in east Baghdad.
The entire city is under curfew, including the airport. The only vehicles allowed out were those carrying the coffins of Thursday's bombing victims.
Thousands of mourners came out onto the streets, walking alongside a seemingly endless fleet of mini-buses, each carrying a coffin on its roof.
The bodies were then driven to an ancient cemetery in the holy city of Najaf, the traditional burial place for Shias, 160km (100 miles) south of Baghdad.
Thursday's multiple car bomb attacks in Sadr City - in which 250 people were also wounded - were the deadliest in Iraq since the US-led invasion of 2003.