The illegal migrants, including children, were spotted at dawn Tuesday by a Frontex patrol boat as it was sailing south of Kythira island.
The migrants, all from Afghanistan, told authorities that they were trying to sail to Italy.
Hania port chief Antonis Daskalakis told ANA-MPA that the Frontex patrol boat had at noon Monday spotted a suspicious boat sailing north of Crete, and when Frontex and Greek coast guard officers approached the vessel on Monday night they found that it was carrying illegal migrants.
Authorities said the group of illegal migrants comprised 10 men, 3 women and 8 children aged 4-15, while 3 Turkish migrant-smugglers aboard were arrested. Two of the Turkish nationals, authorities said, stated that they were simply crew members.
The migrants were taken to the old city hall at Souda, where they were given food and water before being examined by doctors, who found them to be in good condition. The children were taken to Hania hospital for precautionary reasons.