BAGHDAD -- When smoke from the thunderous blast cleared yesterday, little remained of an apartment building in the northern city of Mosul that officials say had been turned into a huge house-bomb that blew up as Iraqi troops searched for weapons.
The blast killed as many as 15 people, injured scores, and came on the day that a car bomb in another northern city killed five. The attacks highlighted the challenge facing U.S. and Iraqi forces as they drive insurgents out of areas farther south, such as Baghdad and Anbar province, only to see them surface in the north.
Military commanders have warned that northern provinces are trouble spots. Nineveh province, whose capital is Mosul, is one of the most worrisome and in recent weeks has been the site of several bloody attacks suspected of being committed by groups loyal to al-Qaida in Iraq. On Monday, a car bomb killed two people south of Mosul, and a blast in the city left five Iraqis dead last week.
"In Mosul ... and the rest of Nineveh province, we still have a very tough fight to go," Maj. Gen. Mark P. Hertling, the commander of U.S. troops in northern Iraq, said at a news briefing this week.
Late yesterday, the casualty toll from the Mosul blast remained unclear. A U.S. military statement put it at 12 dead and 132 injured, with three Iraqi troops among the wounded. Iraqi police said that anywhere from nine to 15 people were killed and at least 70 wounded, most of them civilians.
Police said neighbors had alerted security forces that weapons and ammunition were hidden in the building. When Iraqi troops came to investigate about 4:30 p.m., the building blew up.
It was unclear if the blast was timed to go off as Iraqi forces arrived or if that was a coincidence. "We're not sure if it was a trap or not," said Brig. Gen. Abdul-Kareem Jabouri of the Mosul police.
A police officer in Mosul described the structure as a three-story apartment building overlooking a stretch of road that was notorious for insurgent attacks on Iraqi security forces. Many times, the bodies of Iraqis killed in those attacks had been dangled from an overpass crossing the road, he said.
To deter attacks, Iraqi security forces set up a sniper position atop the building, and the explosion might have been in retaliation, said the official, who declined to give his name because he was not authorized to speak to the media.
Junayed Fajri said his home, nearly a mile from the scene, "was shaken awfully and vigorously. After that I rushed into the street. I saw flames going high in the sky."
"After the explosion, it turned dark," said Amir Fawzi, another local resident. "You can't imagine the magnitude of damage inflicted on the neighborhood."
At least 15 other buildings were damaged in the blast.
Mosul is about 225 miles north of Baghdad. Elsewhere in the north, police said a suicide bomber exploded his vehicle inside a market in Dibis, near the city of Kirkuk. Five people died, and 14 people were injured in the marketplace blast, said 1st Lt. Mohammed Rasheed of the Kirkuk police.
Rasheed said it was the first time that Dibis, about 20 miles northwest of Kirkuk, had been hit by a bomb.
In Baghdad, the targeting of professionals by extremists who consider them sellouts to the U.S.-backed government continued with the assassination yesterday of the dean of the College of Dentistry.
Dr. Mundher Muhhari Radhi had been on the job a week when he was gunned down near his home in central Baghdad.
Police said the killers opened fire from a passing car and witnesses were unable to describe them or the vehicle in the heavy fog and rain. Drive-by gunmen also killed three Iraqi soldiers in northwestern Baghdad.
Tina Susman writes for the Los Angeles Times.