At least 23 people have been killed in a shooting and bombing attack in the Iraqi capital, Baghdad, police say.
Officials fear that the death toll could rise further
Five people were shot dead by gunmen at a car park in the city's busy north-eastern Shaab area.
When people, including nearby police units, rushed to the scene, a car bomb was detonated, killing a further 18.
At least 33 others were wounded in the attack, police said. The car park is often used by worshippers at a nearby Shia Muslim prayer hall.
Some of the injured were severely burned and died before being taken to hospital, police officer Ali al-Obeidi was quoted by the Associated Press news agency as saying.
Officials say the death toll could rise further.
In other violence in the city, at least six civilians were killed and several injured in gun battles between gunmen and police in Baghdad's southern Doura district, Iraqi officials said.
The US military said on Tuesday that three of its soldiers were killed in roadside bomb attacks in and around Baghdad in the past 24 hours.
Jostling for position
Politicians have been expecting an escalation in violence as efforts to form a national unity government move into an intense final phase, the BBC's Jim Muir in Baghdad reports.
The Iraqi Prime Minister-designate, Nouri Maliki, has until next Monday, when the constitutional deadline expires, to complete his cabinet.
It has been an immensely complex task, trying to reconcile the competing claims from the different factions jostling for the best jobs, our correspondent says.
The most contentious and lingering problem has been how to fill the crucial security posts at the ministries of defence and the interior.
Intensive negotiations have so far failed to break the deadlock.
It has even been suggested that the government might be announced with those posts left vacant to be filled in the coming weeks.