Petra's garrison took heavy casualties, but it stood firm until the arrival of a strong army under Mihr-Mihroe relieved the siege.
The Roman archery was very efficient during the siege; as they suppressed the defenders of the town, the sappers were able to approach the walls of Petra.
Lacking enough supplies for his army, Mihr-Mihroe hastily repaired the fallen portion of Petra's wall with linen bags filled with sands, garrisoned the fortress with 3,000 men, left 5,000 men under Fariburz in Colchis to supply the garrison, and himself headed for Persarmenia with the rest of the army.
[5][6] The combined Byzantine-Lazi force, numbering 14,000, defeated Fariburz in a surprise attack, capturing the supplies brought from Iberia by Mihr-Mihroe for Petra.
Dagisthaeus was later stripped of his commands due to his alleged poor leadership of the Byzantines in Petra, and was replaced by Bessas.