A Roman assault against the fort was defeated with heavy losses, and the attackers were only saved by a well-directed charge by
Ostrogothic cavalrymen. As a result, Belisarius decided to institute a blockade by
investing the fort, and in order to secure his besieging forces, he dispatched the Ghassanid Arabs under
Al-Harith ibn Jabalah to raid the region across the
Tigris river. Apparently, he did not trust the Arab king, and sent 1,200 Roman regulars, mostly his own
hypaspistai, to accompany the raiding part. The raiders received information from a captured Persian that Sisauranon has little or no supplies. With this information, Belisarius gained the upper hand in the subsequent negotiation with the Persian garrison. They reached a settlement as the Persians went over to the Byzantine side and were immediately shipped off to
Italy to fight alongside the Byzantine army in the ongoing
Gothic War. The sweltering heat of Mesopotamia caused serious illness in the Roman camp, which forced Belisarius to halt the campaign. The sick were transported back home in carts. The raiding party failed to return or give any information on their movements. Procopius alleged that the Arabs wanted to keep all the booty. ==Aftermath==