BAGHDAD - A suicide car bomb attack on an Iraqi army checkpoint in northern Iraq killed 10 soldiers Thursday, police said, while the U.S. military announced that an U.S. Army lieutenant colonel has been charged with nine offenses, including aiding the enemy in Iraq.

In other developments, seven Iraqis were killed and 14 wounded in two other bomb attacks by suspected insurgents.

The Iraqi army checkpoint attack occurred about 9 a.m. in Khalis, 50 miles north of Baghdad. The city is located in Diyala province, which has seen some of the worst violence recently as mostly Sunni militants are believed to have fled to the area since U.S. and Iraqi troops launched a security crackdown in Baghdad on Feb. 14.

On Wednesday, four Iraqi police officers were killed when a suicide bomber struck a police station in the Diyala city of Balad Ruz, 45 miles northeast of Baghdad. Two days earlier, a double-suicide bombing struck a paratrooper outpost in the province, killing nine U.S. troops. An al Qaeda-linked group claimed responsibility.

Meanwhile, the U.S. military said Thursday that a senior U.S. officer has been charged with nine offenses, including aiding the enemy and fraternizing with the daughter of a detainee while he commanded a military police detachment at an American detention facility near Baghdad.

Army Lt. Col. William H. Steele was accused of giving "aid to the enemy" by providing an unmonitored cell phone to detainees.

Steele was the commander of the 451st Military Police Detachment at Camp Cropper, a U.S. detention center on the western outskirts of Baghdad, when the offenses allegedly occurred between October 2005 and February, military spokesman Lt. Col. James Hutton said.

Steele was being held in Kuwait pending a grand jury investigation, Hutton said.

The other charges included unauthorized possession of classified information, fraternizing with the daughter of a detainee, maintaining an inappropriate relationship with an interpreter, storing classified information in his quarters and possessing pornographic videos, the military said.

Steele also was charged with improperly marking classified information, failing to obey an order and failing to fulfill his obligations in the expenditure of funds, the military said.

Camp Cropper, located near the Baghdad airport, replaced the notorious Abu Ghraib prison as the main detention facility in the capital area.

In other violence on Thursday, two suicide bombers attacked an office of the Kurdistan Democratic Party of Massoud Barzani, leader of the autonomous Kurdish region in Iraq, killing three of its guards and wounding five, police said.

The casualties could have been higher if guards had not opened fire on the two attackers, forcing them to detonate their explosives at least 50 yards from the office, police said.

The attack occurred at about 8 a.m. in Zumar, a town that is 45 miles west of Mosul, the capital of Ninevah province. It was the second suicide attack this week aimed at the KDP in that area.

On Monday, a suicide car bomber attacked a KDP office in another town near Mosul, which is 225 miles northwest of Baghdad, killing at least 10 people and wounding 20.

In a separate attack in Mosul on Monday, suspected insurgents assassinated a local KDP official in a drive-by-shooting, police said.

In central Baghdad, a roadside bomb missed a passing police patrol on Thursday but killed four civilians and wounded nine in a commercial district, police said.

A funeral procession also was held in the Shiite neighborhood of Sadr City for an Iraqi who locals said was killed in an attack by the U.S. Air Force early Thursday morning. AP television footage showed three large craters in the ground of a commercial area and several damaged shops.

The U.S. military said it was checking the report, but could not immediately confirm it.