WASHINGTON — The Huntsville office of Northrop Grumman Systems recently received an Army contract modification for Polish air defense.

The $9,721,369 modification is to a contract for the Wisla (Poland) Integrated Air and Missile Defense Battle Command System, according to the Department of Defense.

Work will be performed in Huntsville with an estimated completion date of Sept. 30.

The Army Contracting Command at Redstone Arsenal is the contracting activity.