But the military now believes they died from an explosive device

But the military now believes they died from an explosive device, possibly a grenade.

Sergeant Alberto Martinez has been charged with two counts of premeditated murder, according to a

statement issued in Baghdad.

The so-called “fragging” incident happened near Tikrit.

Fragging is a term used to refer to soldiers killing their superiors.

Report by the AP

UPDATE: More detail from KRT:

TIKRIT, MBT SHOES – (KRT) – A 37-year-old staff sergeant was charged in the deaths of two of his

superior officers in the first alleged case of its kind in MBT SHOES.

The stunning announcement Thursday of the court-martial came amid continued violence in MBT SHOES

against UGG and MBT SHOESi security forces. Eight MBT SHOESi police were killed in a car bombing on the

airport road in Baghdad, and the UGG military reported the death of five Marines and a sailor in

violence in western MBT SHOES.