MILWAUKEE - The man responsible for the worst mass shooting on a military facility in U.S. history was scheduled to be deployed overseas with a Madison-based reserve unit and two other reserve units.

Maj. Nidal Malik Hasan was to be sent to Afghanistan with Madison's 467th Medical Detachment, the 1908th Medical Detachment from Topeka, Kansas and the 1493rd Combat Stress Detachment from Durham, North Carolina.

All three reserve units specialize in helping soldiers at war who experience severe stress.

Maj. Claudia Jefferson, an Army Reserve Command public affairs officer, said all three of these units and Hasan would be traveling over together and working together with members providing their different talents.

Hasan is listed as active duty medical personnel.

He did not belong to any of the three reserve units, but was "tagged" to join with them because no one in the three units had his psychiatrist credentials, Jefferson said.

The filler program places active duty personnel in positions that cannot be filled by reserve units. In this case, the group was short a psychiatrist. Hasan was "tagged" to join the units.

Jefferson told TMJ4's Tom Murray the Army is short on psychologists, psychiatrists and social workers.