The armed woman was firing a gun when two officers encountered her at the apartment complex in Newark on Friday night, the New Castle County police department said in a news release.
Both officers opened fire on the woman, hitting her in the chest, police said. She was taken to a hospital, where she was in critical condition, according to the release.
Investigators believe the woman had shot a 26-year-old woman during an argument. The other woman also was in critical condition at a hospital, police said.
Neither woman's name was immediately released.
Both officers who fired their weapons were placed on administrative leave, a standard procedure, the Delaware News Journal reported.