A suicide car bomb attack on the Iraqi national guard headquarters in Kirkuk has killed 23 people, officials say.
Police in Kirkuk have become the latest targets of militants
The victims in the northern city were queuing to apply for jobs, said a general in the national guard.
Bloodied bodies were strewn across the street, which was littered with twisted metal and shards of glass.
Elsewhere, there were repeated attacks on US soldiers near Baghdad airport and US planes carried out fresh strikes on the restive city of Falluja.
The attacks came on the day Iraqi Airways flew its first international flight into Baghdad airport for 14 years. It is not clear if there was any connection.
In other developments:
- A senior Iraqi oil official, Mohammed Zibari, survives an assassination attempt in Mosul, but five of his bodyguards are killed, police say
- A roadside bomb in Baghdad, kills one
person and wounds two others, police say
- In Baquba, nine people are reported injured when a mortar shell is fired at a crowd of parents and schoolchildren awaiting exam results at a school
- British troops clash with supporters of cleric Moqtada Sadr in Basra for a second day
- Arab Shia leader Sheikh Kadhim al-Hany is ambushed and killed in Kirkuk, police say.
The Kirkuk attack caused devastation and heavy casualties.
"I saw a speeding car crossing an open field heading
toward the would-be recruits, then there was a huge
explosion and a big fire," said Asu Ahmed, a street
"There were many dead and injured people and I
helped put them in ambulances."
Falluja residents inspect a crater left after a US air strike
The attack was the latest to be directed at police targets in Iraq. On Tuesday, 47 people were killed in an attack at a Baghdad police station, and on Friday, at least three policemen died when a roadblock was blown up.
Twelve officers were killed in an ambush in Baquba earlier in the week.
The BBC's Mike Donkin in Baghdad says insurgents have made security personnel their main targets, as the new Iraqi government attempts to build forces capable of maintaining order in Iraq.
Two US soldiers were killed and eight injured when their military convoy was hit by a car bomb on the main road to Baghdad airport.
They had been travelling to the scene of another car-bombing 30 minutes earlier, in which three soldiers were hurt.
In the latest of a series of attacks on Falluja, the US launched an airstrike on a checkpoint linked to Abu Musab al-Zarqawi, the US military said in a statement.
"The illegal checkpoint used blockades to disrupt security, intimidate and harass local citizens and interrogate and detain local civilians," the statement said, after the operation on Saturday evening.
"Evidence indicates Iraqi citizens have been kidnapped at such checkpoints, taken to outlying areas where they were forced to dig their own graves and then executed," it added.
There were no reports of casualties.