When Cleomenes saw that the Argives did whatever was signalled by his herald, he commanded that when the herald cried the signal for breakfast, they should then put on their armor and attack the Argives.

The Lacedaemonians performed this command, and when they assaulted the Argives they caught them at breakfast in obedience to the herald's signal; they killed many of them, and far more fled for refuge into the grove of Argus, which the Lacedaemonians encamped around and guarded.

Then Cleomenes' plan was this: He had with him some deserters from whom he learned the names, then he sent a herald calling by name the Argives that were shut up in the sacred precinct and inviting them to come out, saying that he had their ransom. (Among the Peloponnesians there is a fixed ransom of two minae to be paid for every prisoner.) So Cleomenes invited about fifty Argives to come out one after another and murdered them.