Fort Riley ? Three members of a military transition team from Fort Riley have been killed in an attack in Afghanistan.

Fort Riley officials announced Thursday that two National Guardsmen and a soldier were killed when they were attacked by insurgents during operations in Jalalabad on Monday.

Killed were Maj. Henry San Ofeciar, 37, of Agana, Guam, and two Pennsylvania National Guardsmen – Sgt. 1st Class Scott Ball, a 38-year-old combat engineer from Mount Holy Springs, Pa., and Sgt. Jan Argonish, a 26-year-old infantryman from Peckville, Pa. Ball and Argonish were assigned to the 55th Brigade in Scranton, Pa.

The three men were part of small teams that help train and advise military and police forces in Iraq and Afghanistan. Team members train at Fort Riley for 60 days before going overseas for a year.

The deaths bring the number of soldiers killed in Afghanistan or Iraq from Fort Riley to 126. In addition, an Air Force airman was killed in Afghanistan.

Ofeciar was a finance officer making his first deployment overseas, while Ball and Argonish were both on their second tours.