Battle of Ulai

The Battle of the Ulai River, in 652 BC, during the reign of Ashurbanipal was an Assyrian assault on Elam, which was a Babylonian ally, and was apparently motivated by a desire to protect vital trade caravans of horses and metals from the mountains of Iran and Eastern Anatolia. The Elamite Army was decisively defeated, leading to the complete destruction of Elam shortly thereafter.

Reference: IRAN: Historical Introduction