History of the Peloponnesian War

So the Athenian ambassadors returned to their forces: and their generals, since the Melians did not listen at all to their proposals, immediately proceeded to apply themselves to war; and having divided the work between the different states, enclosed the Melians with lines on all sides.

Afterwards, the Athenians left a part of their own troops and the allies, to keep guard both by land and sea, and returned with the main body of the forces. Those who were left behind remained and besieged the place.