Updated

One of the largest bombing campaigns of the war destroyed extremists' "defensive belts" south of Baghdad, allowing American soldiers to push into areas where they have not been in years, a top commander said Friday.

The day before, two B1-B bombers and four F-16 fighter jets dropped 48 precision-guided bombs on 47 targets, U.S. Air Force Col. Peter Donnelly, commander of the 18th Expeditionary Air Support Operations Group, told reporters in Baghdad.

The targets consisted mainly of weapons caches and powerful roadside bombs buried deep underground — key defensive elements for Al Qaeda in Iraq insurgents, said Donnelly and Army Col. Terry Ferrell, commander of the 2nd Brigade Combat Team, 3rd Infantry Division.

Extremists were believed to have controlled Arab Jabour, a Sunni district lined with citrus groves, but Ferrell said "the predominant number" have now fled to the southwest since his troops' operations began Jan. 1.

"We're moving into areas where coalition forces have not been in months or years in some cases," Ferrell told reporters via a video link, adding that insurgents "had established a deliberate defensive belt to deny our movement in the area."

Ferrell said the southwest is "where we take this fight to next. It is all about fighting the enemy where the enemy wants to go."

As U.S. and Iraqi ground forces move through areas to push out insurgents, Ferrell said members of the so-called "Awakening Council" movement — mostly Sunni fighters who switched sides to join in the fight against Al Qaeda — will be relied upon to stabilize the region and maintain security.

It was those Sunni fighters, Ferrell said, who largely provided the intelligence that allowed U.S. forces to locate the targets destroyed in Thursday's bombing.

Despite the massive size of the airstrikes, Donnelly said that to the military's knowledge, no civilians were killed. That could not immediately be independently confirmed. He added that the targeting of three targets was called off because unmanned surveillance planes showed civilians in those areas.

Donnelly said it wasn't yet known how many insurgents were killed in the attacks.

But Mustapha Kamil Shibeeb al-Jibouri, leader of Arab Jabour's Awakening Council, said the airstrikes killed at least 21 Al Qaeda militants including a group leader.

"Their bodies are still in the area. They have not been evacuated yet," he told The Associated Press.

After Thursday's fierce airstrikes, soldiers discovered two houses used to torture kidnap victims and arrested at least 12 suspected insurgents, according to an Iraqi officer.

The bombing campaign was part of a nationwide operation that the U.S. military began on Tuesday in an effort to rid Iraq of Al Qaeda fighters.

Little initial resistance has been reported, though at least nine U.S. soldiers have been killed since the offensive began — the deadliest days for American forces since last fall.

In the farming village of Zambaraniyah, on the outskirts of Arab Jabour about 15 kilometers (nine miles) southeast of the capital, scenes of neglect and devastation were testimony to years of fighting between militants and U.S. and Iraqi troops. Most of the land is torched or left fallow along small roads that were once laced with booby traps and bombs. Fields are strewn with trash and the blackened hulks of cars. Many buildings are pockmarked by gunfire, and most homes are abandoned.

Maj. Alayne Conway, a spokeswoman for troops in central Iraq, said the amount of ordnance dropped in 10 minutes nearly exceeded what had been used in that region in any month since last June.

Conway said the air attack "was one of the largest airstrikes since the onset of the war" in March 2003.

An AP reporter in Zambaraniyah observed that the bombing continued until Thursday evening.

Even before Thursday's massive attack, U.S. Army Lt. Col. Mark Solomon told a small group of reporters in Zambaraniyah that residents were returning to their homes and that stores and schools were reopening.

Despite the apparent success to move quickly into suspected Al Qaeda zones, the overall impact of the current campaign remains unclear.

Before the beginning of the offensive, many militants apparently fled U.S. and Iraqi forces massing north of Baghdad in Diyala province — another area around the capital where insurgents continue to hold sway. The retreat left open the possibility that Al Qaeda and its backers will seek new staging grounds in northern Iraq, where U.S. troop levels are lower.

The military announced Friday that coalition forces killed two insurgents and detained 11 suspects over the past two days in central and northern Iraq.

Meanwhile in northern Iraq, Turkish artillery shelled a Kurdish area near the Iraqi-Turkish border, said Jabar Yawer, a spokesman for the Kurdish Peshmerga militia. The shelling started Friday at dawn and lasted one hour in the Amadiya area of Dahuk province. Kurdish authorities were not able to confirm any possible damage because of the bad weather.

Separatist rebels of the Kurdistan Workers' Party, or PKK has waged a war for autonomy in parts of Turkey for more than two decades, a conflict that has cost tens of thousands of lives, and its fighters have bases in Kurdish sections of northern Iraq.