HAMPTON, Va. - An Air Force enlisted man was sentenced yesterday to 10 years in prison for killing an airman from Gloucester County in their living quarters in Iraq by shooting him in the chest with a 9mm pistol.

Kyle J. Dalton also was given a dishonorable discharge and a reduction in rank from senior airman to airman basic and ordered to forfeit all pay and allowances, said Maj. John Elolf, an Air Force spokesman.

Dalton pleaded guilty Monday to involuntary manslaughter and violating a lawful general regulation by drawing or aiming a firearm when deadly force was unnecessary. He faced up to 12 years in prison.

In exchange for the plea, Air Force prosecutors dropped charges of murder, which carried a maximum punishment of life in prison, and assault.

Dalton told the judge at his court-martial that he thought his service pistol was unloaded when he pointed it, playfully, at 22-year-old Senior Airman Carl J. Ware of Glassboro on July 1, 2006, and pulled the trigger.

Ware and Dalton were stationed at Hickam Air Force Base in Hawaii and were part of the 886th Expeditionary Security Forces Squadron at Camp Bucca, where they guarded detainees.

The Air Force held the court-martial at Langley Air Force Base in Hampton to make travel easier for witnesses.

The service declined to release Dalton's age and hometown, citing privacy regulations.