The U.S. Army Wednesday charged three of its soldiers with murder for their role in the execution-style slayings last year of four Iraqi prisoners.

Authorities say the Iraqi men were handcuffed, blindfolded and shot in the head in April, 2007.  The bodies were thrown into a Baghdad canal.

The New York Times reported in August that U.S. military officials detained the Iraqi men after an exchange of small arms fire, but ordered them to be released because of a lack of evidence.

The newspaper reported that, according to sworn statements, the soldiers instead murdered the Iraqi prisoners to avenge the deaths of two soldiers from their unit.

The U.S. suspects include Sergeant John Hatley, 40, Sergeant First Class Joseph Mayo, 27, and Sergeant Michael Leahy, 26.  All were formerly assigned to the First Battalion, 18th Infantry Regiment.

Four other soldiers from the unit have been charged with the murder conspiracy for allegedly going along with the slayings.

Some information for this report was provided by AP.