The illegal migrants, who told authorities they are from Egypt, were rescued from a distressed vessel in the early hours of Saturday by the Iceland-flagged "OPV Aegir" taking part in the Frontex "Poseidon 2011" joint European operation, which was patrolling the region at the time.
The Search and Rescue Coordination Center was informed early Saturday of a distressed vessel southwest of Crete with an unknown number of migrants, and immediately alerted the Frontex vessel patrolling the area.
The Frontex patrol boat spotted the distressed vessel at noon on Saturday at a distance of 80 nautical miles west-southwest of Crete, and picked up the 94 people on board the distressed vessel and transported them to the Port of Piraeus.
The Frontex vessel arrived at Piraeus port on Sunday morning, where it disembarked the 94 people in the presence of port authority and police officials, which took the 90 illegal migrants into custody.
The other four persons were arrested on charges of migrant-smuggling and will be taken before a public prosecutor.