RIVERSIDE, Calif. (AP) — Riverside County authorities say a sheriff's deputy fatally shot a knife-wielding man caught beating a woman over the weekend.

Officials said in a statement that the deputy responded Sunday morning to reports of an assault in an open field near Desert Hot Springs.

The deputy called for backup after finding the man attacking the woman and threatening to stab her.

Officials say the deputy opened fire when the suspect ignored orders to drop the weapon.

The suspect, who was not identified, died at a hospital. The woman was treated for non-life-threatening injuries.

The incident is under investigation.