The discovery was made Wednesday at Joint Base Lewis-McChord from inventories of a Stryker brigade, part of the 4th Brigade, 2nd Infantry Division, base spokesman Matt Hinkle told The (Tacoma) News-Tribune.
The missing items are not weapons, but accessories such as laser gun sights, the Army said. Details of the items and their value weren't disclosed.
However, the Army posted a $10,000 reward for information leading to the recovery of the items.
Members of the Army's Criminal Investigative Division are at the base while the entire 100-member company remains confined to barracks and the dining hall, I Corps spokesman Maj. Chris Ophardt said. Family members are allowed to visit the soldiers, he said.
The 4th Brigade has done two tours in Iraq, but doesn't have any current deployment orders, the report said.