As a result of bad communication, Himera believed the Athenians had abandoned their oath to assist them, and prepared themselves to surrender. Many of the military commanders fled the city through secret tunnels, unaware of the reinforcement army. Finally, the Athenian reinforcements arrived in mid-February, and camped behind the Syracuse army. Alextrus, under orders from Syracuse to execute the assault, attacked the walls with half his force, while striking the Athenian's in a night attack. The Athenians were able to re-form slightly, marching into phalanx formation, but quickly became encircled. The expedition force was decimated, with no record of Athenian survivors.