Updated

City prosecutors say all charges have been dropped against Arizona's All-America running back Ka'Deem Carey in a domestic violence case.

Carey was facing misdemeanor assault and disorderly conduct charges stemming from an alleged domestic violence incident in December involving his ex-girlfriend.

The Tucson City Prosecutor's Office issued a statement Friday saying it was dismissing all charges against Carey.

The statement said that "a key witness for the prosecution is unavailable and even if the witness were available, there is no substantial likelihood that a judge would convict Mr. Carey."

As a sophomore for the Wildcats last season, Carey led the nation in yards rushing with 1,929 and set a school record with 23 touchdowns.

He nearly became the 16th running back in NCAA history to reach 2,000 yards in a season.