Pro-Palestinian activists say Greek authorities have intercepted a ship that set sail from a Greek port to try and break Israel's naval blockade of the Gaza Strip.
The activists say the Greek coast guard blocked the ship Tahrir on Monday, as it tried to leave the island of Crete in defiance of a government ban on flotilla vessels.
Greece announced the ban last week on boats and ships headed to Gaza and arrested the captain of a vessel carrying U.S. pro-Palestinian activists for leaving port without permission on Saturday.
The Tahrir is named after a Cairo square at the center of an Egyptian anti-government uprising earlier this year. The ship was carrying activists from Canada and other nations when it was intercepted.
Organizers had planned to send about a dozen vessels from Greece to Gaza late last month, carrying hundreds of activists and humanitarian aid for the Palestinians.
But the flotilla has suffered a series of setbacks, with some ships facing technical and bureaucratic problems. The activists accuse Israeli spies of sabotaging their mission, a charge Israel denies.
Israel has vowed to enforce a naval blockade it imposed on Gaza in 2007 to stop weapons from reaching Hamas militants that run the territory.
The Greek government has offered to deliver the flotilla's humanitarian cargo to Gaza through organized channels that include Israeli ports, where the cargo is screened for potential weapons. Organizers have rejected the idea.
Some activists on a French boat protested the Greek ban on the flotilla by revving up the engines on Monday. But, the activists did not attempt to move from the boat from its position, docked at the Greek port of Piraeus.
Some information for this report was provided by AP, AFP and Reuters.