LITTLE ROCK (AP) — The Arkansas National Guard now says 35,000 current and former soldiers are at risk of identity theft because of a missing computer hard drive.

The Guard had initially thought the hard drive contains information on soldiers in two battalions of the 39th Infantry Brigade. But in a statement released Thursday the Guard now says the device has information all soldiers who've served in the Arkansas National Guard since 1991.

An information management team is putting together a list of those affected so they can be notified. Letters are expected to be mailed early next week.

Capt. Chris Heathscott says an investigation is under way into how the hard drive was lost — but says there is no evidence it was stolen.