When Tahir pushed into the city, al-Amin sought to negotiate safe passage out. Tahir reluctantly agreed on the condition al-Amin turn over his sceptre, seal and other symbols of office. Al-Amin tried to leave on a boat, apparently with these symbols, rejecting warnings to wait. However, Tahir noticed the boat, and Al-Amin was thrown into the water, swam to shore, was captured and then brought to a room, where he was executed. His head was placed on the Anbar Gate. Al-Tabari (v. 31 pp. 197–202) quotes Tahir's letter to al-Ma'mun informing him of al-Amin's capture and execution and the state of peace resulting in Baghdad.