Iraq's new interim parliament has ended its first session without taking a vote on a new government after the parties failed to agree on its make-up.
The muffled blasts did not hold up the opening of the assembly
Talks between the Shia and Kurd parties which won the 30 January poll, the first since the fall of Saddam Hussein, are bogged down over Kurdish issues.
The session ended after the 275 deputies were sworn in.
A series of mortar attacks near the venue in Baghdad's fortified Green Zone failed to disrupt proceedings.
Negotiators say the parties in the Transitional National Assembly hope to reach an agreement by the end of the month.
A car bomb earlier on Wednesday killed three Iraqi soldiers and wounded seven other people at an army checkpoint in the town of Baquba, 60km (35 miles) north-east of Baghdad.
During the mortar attack, windows in the Saddam-era convention centre rattled and lights flickered as sirens howled outside.
The assembly session opened at 1130 (0830 GMT) with Koranic verses and closed a few hours later with no date fixed for the next meeting.
The BBC's Jim Muir in Baghdad says coalition politics is a novelty in a country ruled by a tight dictatorship for decades, and the learning curve has been steep.
Politicians across the board, aware of rising public impatience, agreed to hold the inaugural meeting in order to give at least a semblance of progress, our correspondent adds.
Once it agrees on a government, the assembly must see through a new constitution in time for a general election in December which is meant to produce a permanent National Assembly.
The Shia United Iraqi Alliance, which won just over half the seats in the transitional assembly, has been locked in talks for several weeks with the Kurdish bloc.
The main sticking points are over the fate of Kurdish fighters and the northern city of Kirkuk.
16 March: Transitional National Assembly to meet for first time
Late March: Government due to be formed
15 August: Draft constitution (six-month extension possible)
15 October: Possible referendum on constitution
By 15 December: Elections for government
Iraqi Arabs have been calling for the Kurdish fighters to be disbanded or integrated into the Iraqi national army.
The argument is essentially about who controls the oil revenues in the Kurdish-dominated city.
Shia Muslims and Kurdish leaders are poised to take a dominant role in national politics after years of dominance by the minority Sunni Muslims.
Wednesday is the anniversary of the Saddam Hussein regime's poison gas attack on Kurdish civilians at Halabja in 1988, in which 5,000 people died.
"Today, on this occasion, we celebrate the inauguration of parliament after the fall of this regime," Kurdish member Fuad Masoum told the assembly.