Bombers killed an Iraqi police colonel yesterday, the commander of a US-trained police rapid intervention team in the southern city of Hilla.
Iraq has seen what US military spokesman called a "tremendous spike" in killings in the Muslim holy month of Ramadan, warning that the surge in sectarian and insurgent violence "will still get worse before it gets better."
Police found the corpses of 36 murder victims on the streets of Baghdad on Thursday, according to a US military spokeswoman.
Dr. Haidar Timimi at Hilla's main hospital confirmed the death of Colonel Salaam Maamuri and said that eight wounded officers were also receiving treatment.
Maamuri survived several previous assassination attempts. His squad was set up with US support to fight insurgents in an area south of Baghdad, including a region which became notorious as the "Triangle of Death".
In recent months Iraqi police have borne the brunt of insurgent violence directed at Iraq's US-backed coalition government, but it is unusual that bombers would manage to plant a device inside a headquarters building.
Gerald Burke, a US police expert seconded to the Iraqi interior ministry as an advisor, told an audience in Chicago on Thursday that Iraq's police force has budgeted to lose 25 officers a day to death or serious injury.
In other attacks yesterday, masked attackers gunned down and killed three Shiite youths standing by a cigarette stand in Kirkuk, police Captain Imad Jassim Khudir said.
Hesaid the dead youths were thought to be supporters of radical Shiite cleric Moqtada al-Sadr, whose Mehdi Army militia is accused of taking part in sectarian attacks and clashes regularly with US and Iraqi security forces.
Al-Sadr said yesterday that he would denounce any members of his own militia who are found to have taken part in a spate of death squad killings against Iraqis.
"There are rumors that there are groups or persons from the Mehdi Army are attacking the Iraqi people with no right to do so," Sadr said in a statement bearing his signature distributed by his office in Najaf.
"It is not proved so far but, if proved, I will declare their names and will renounce them with no fear or hesitation," he said.
Meanwhile, suspected Shiite militiamen, some dressed as police, broke into a TV station and gunned down 11 executives, producers and other staffers on Thursday. It was the deadliest attack against the media in Iraq, where at least 81 journalists have been killed in the past three years.
The station, Shaabiya, was new and had not yet started full broadcasting. So far it had only aired test programming.
Around two dozen gunmen, some in police uniform, pulled up to the Shaabiya offices at 7am on Thursday in civilian cars, stormed into the building and killed most of those inside, said the station's executive director, Hassan Kamil, who was not there at the time.
Staff had been working around the clock to get the station ready to begin broadcasting at the end of Ramadan, so many were in the office, some of them still sleeping at the time of the attack.
The gunmen fired some 100 shots, Kamil said. But survivors reported not hearing any shots and no windows were damages, suggesting the attackers may have used silenced pistols and killed their victims at close range, he said.
There were two wounded survivors -- the program director and chief producer -- who were in the hospital in critical condition.