Bombings, ambushes escalate in Baghdad
12 people killed in market; Iraqi officials assassinated
A series of bombings across Iraq continue.
Iraqis looking for jobs line up at recruiting stations.
U.S. troops in western Iraq encounter well-trained fighters.
BAGHDAD, Iraq (CNN) -- Insurgents killed 12 people in a suicide car bombing at a crowded Baghdad marketplace and assassinated two top Iraqi security officials Thursday -- the latest incidents in an escalation of bombings and ambushes.
"Those of us who have covered wars here and there over the past 15, 20, 25 years have to struggle to think of anywhere where we've seen such a relentless brutality," John Burns, a reporter for the New York Times said on CNN.
"Of course, Pol Pot in Cambodia, Rwanda -- things on a much larger scale than this. But this is pretty bad."
The escalation follows the establishment of the Shiite-led transitional government two weeks ago.
Burns described the insurgency, generally regarded as Sunni Muslim, as "absolutely ruthless, relentless" in its effort to prevent the government from consolidating its power.
"This is the moment they [insurgents] have fought to avoid these past two years -- power shifting to the Shiite majority," said Burns, who is the Times bureau chief in Baghdad.
Burns said insurgents have been picking targets that are specifically Shiite -- security forces, mosques, casual workers, weddings and funerals.
The two Iraqi ministry officials were killed in separate incidents Thursday morning in Baghdad.
Brig. Gen. Iyad Imad Mahdi with the Ministry of Defense was on his way to work when he was gunned down in a western neighborhood, police said.
Col. Jamal Ahmed Hussein was killed in the al-Amin neighborhood as he headed to the Interior Ministry.
The suicide car bombing struck a marketplace at a busy intersection near a mosque, post office and movie theater in eastern Baghdad's al-Jadida neighborhood. Besides the 12 people killed, 56 were wounded.
A few hours later a suicide car bomber targeted a U.S. military convoy along a highway in western Baghdad, wounding five civilians, police said. There was no word on American casualties.
Two U.S. Marines were killed and 14 others wounded when a bomb struck their armored vehicle Wednesday evening during the counter-insurgency offensive near the western border with Syria that began over the weekend, the military said.
So far, five Marines have been reported killed in the operation.
Washington Post correspondent Ellen Knickmeyer, embedded with the Marines, reported in Thursday's edition that she was in the vehicle, which can carry as many as 18 troops, until minutes before it exploded in an orange ball of fire.
The bombing happened east of the town of Husayba near the Euphrates River, the military said.
Knickmeyer wrote that the dead and wounded troops were part of the Marines' 1st Platoon, Lima Company, 3rd Battalion, 25th Regiment -- a reserve unit based in Columbus, Ohio.
At least 60 percent of the platoon's troops have been killed or wounded in this week's fighting, Knickmeyer quoted the platoon commander as saying.
Another reporter embedded with the Marines, Solomon Moore of the Los Angeles Times, told CNN that troopers sweeping through towns near the Euphrates River near Syria have turned up weapons caches and fighting positions but not many insurgents.
In fact, the fighters appear to be on the run, and some observers think they could have fled over the border into Syria.
Elsewhere Thursday, three U.S. soldiers died in separate roadside bombings in eastern Baghdad, near al-Musayyib and near Samarra.
The deaths brought to 1,613 the number of American troops who have died since the war began more than two years ago, according the military.
Other developmentsIraqi and U.N. authorities have released a survey of living conditions in Iraq last year that reports "deteriorating physical and social conditions." (Full story)Iraqi security forces have captured a financier for Jordanian-born militant Abu Musab al-Zarqawi's terror network, the Iraqi government said Thursday. Amar Farid Abd-al Qadir 'Ashur al-Jaburi was arrested in Mosul on April 15, officials said. A U.S. Senate committee probing the defunct U.N. oil-for-food program in Iraq alleges that two politicians from Britain and France received millions of dollars' worth of oil allocations from Saddam's regime. France's Charles Pasqua and Britain's George Galloway have denied the allegations. (Full story)Operation Cobweb, conducted by Polish and Iraqi soldiers, resulted in the detention of 29 suspected insurgents and the seizure of weapons in Wasit province.
CNN's Kevin Flower, Enes Dulami and Kianne Sadeq contributed to this report.