A sergeant with B Company of the 4th Battalion, 9th Infantry Regiment and an interpreter talk with an Iraqi man outside Baqouba on Tuesday on the opening day of Arrowhead Ripper. Elements of the 4-9, part of the 4th Brigade, 2nd Infantry Division, are taking part in the operation led by their Fort Lewis comrades from 3rd Brigade. This is one of several Army photos moved by The Associated Press from the Diyala Province operation. Associated Press Photo: Staff Sgt. Antonieta Rico/U.S. Army

Got word back this morning from Maj. Rob Parke on the 3rd Brigade staff, who provided a rundown of the units involved and the first hours of the operation.

Mainly it is the 5th Battalion, 20th Infantry Regiment, which has led a battalion-sized task force in eastern Baqouba since March, and the 1st Battalion, 23rd Infantry Regiment, which moved up the 55 miles from Baghdad on Monday and rolled into the fight that night and the following morning.

"By dawn all initial assault objectives had been seized. Though quiet during the early morning hours, elements of TF Arrowhead were in enemy contact throughout much of the day," Parke wrote. Stryker troops were hit by one complex attack -- a large, buried IED followed by small arms fire –- and were attacked about 10 other times by small arms fire and three other bombs.

He said troops found and destroyed 16 other roadside bombs, four houses that had been rigged to explode, and two car bombs. They found two safe houses, destroyed what he described as a mobile weapons cache, and captured two other weapons caches, including "a significant IED cache."

He said 3rd Brigade soldiers killed 24-36 enemy fighters and detained nine.

Twelve Arrowhead soldiers were wounded – eight were returned to duty and four were evacuated to the combat support hospital in Balad. The one U.S. soldier killed in the first day of the operation was not from a Fort Lewis unit.

About 2,000 U.S. and 500 Iraqi Army soldiers are involved in the attack.

The brigade headquarters and the 296th Brigade Support Battalion have moved up from Baghdad to FOB Warhorse in Baqouba, as has the 1-23.

The 2nd Battalion, 3rd Infantry Regiment remains in Baghdad where it is conducting clearing operations in the Rashid security district in the south central part of the city, working under the direction of the 4th Brigade, 1st Infantry Division.

The 1st Squadron, 14th Cavalry Regiment is also in Baghdad, where it is supporting the 2nd Brigade, 1st Cavalry Division in the Karkh, or Haifa Street, area of the city.

The 1st Battalion, 37th Field Artillery is in Taji and continues to work in that area in support of the 1st Brigade, 1st Cavalry Division. U.S. military officials in Baghdad announced Wednesday that gunners from C Battery nabbed the alleged leader of a local bomb-making cell on Tuesday.