ATHENS - A major rescue operation was underway off the south coast of Crete island on Friday, as water has entered a wooden vessel carrying some 700 migrants and refugees at initial estimate, the Greek Coast Guard said.

Approximately 250 people have already been evacuated from the sea, about 75 nautical miles off Kali Limenes in Crete, local officials told Greek national news agency AMNA.

Greek Coast Guard vessels, a navy airplane and a Super Puma helicopter were dispatched for the mission. Four ships sailing around also offered help.

The Italian Coast Guard was initially alerted about the incident, according to Athens officials, as the wooden vessel was sailing in international waters.

It is believed that the ship was on its way from North Africa to Italy.