In August 476, Zeno besieged Constantinople.[23] The Senate opened the gates of the city to the Isaurian, allowing the deposed emperor to resume the throne. Basiliscus fled to sanctuary in a church, but he was betrayed by Acacius and surrendered himself and his family after extracting a solemn promise from Zeno not to shed their blood. Basiliscus, his wife Aelia Zenonis and his son Marcus were sent to a fortress in Cappadocia,[24] where Zeno had them enclosed in a dry cistern, to die from exposure.[1][25]