Police in Baghdad say five people have died in a bomb attack outside a state-owned bank in the Shi'ite Sadr City area.
Authorities said the explosion took place mid-morning as the victims stood in line to collect their pensions. At least 12 others were wounded.
Separately, a sandstorm brought down an Iraqi military helicopter near Karbala, killing at least four soldiers.
Tuesday, the top U.S. military officer, Admiral Mike Mullen, visited Iraq and said he was impressed by the role Iraqi security forces have taken since U.S. troops pulled out of the main cities last year.
He says violence is down significantly from one year ago and has reached its lowest level since 2003.
Also Tuesday, Iraq's parliament postponed what would have been only its second meeting since parliamentary elections in March.
Lawmakers said they were unable to agree about who should form a new government.
The delay extends the political deadlock that has plagued the country since the March election.
No date has been set for the next meeting of Parliament.
Admiral Mullen met with Iraqi military and government leaders during his visit. Those leaders include Defense Minister Abd al-Qadir Muhammad al-Mufriji, incumbent Prime Minister Nouri al-Maliki and former Prime Minister Ayad Allawi.
Mr. Allawi's Sunni-backed Iraqiya alliance won 91 seats in parliament in the March elections. Mr. Maliki's Shi'ite-dominated State of Law alliance captured 89 seats. Both groups were far short of the 163-seat majority needed to govern, and each has been trying to form a ruling coalition.
Under Iraq's constitution, the parliament should have picked a president two weeks ago. The president would then have chosen a prime minister and asked him to form a government.
Some information for this report was provided by AFP, AP and Reuters.