The Togo-flagged Lebanese ship carrying humanitarian aid to Gaza, including 1,100 units of blood, was intercepted by Israel's navy on Thursday and was towed to the Israeli port of Ashdod after being surrounded by naval gunboats.
There were eighteen people, of Syrian, Lebanese, Indian and British origin, on board the ship. They were mostly deported according to their nationalities, although an 84-year-old former Catholic archbishop of Jerusalem, Monsignor Hilarion Capucci, was among those who were sent to Syria.
Media reports said Israeli forces beat some of the activists. The units of blood were sent into Gaza, while the rest of the supplies were being examined before possibly being sent on to the enclave. No weapons were found on the ship, the Israeli military said.
The Israeli navy had initially "prevented the ship from entering Gaza waters" and ordered the vessel to head for Egypt, but the crew failed to obey, the Haaretz newspaper quoted Israeli Defense Minister Ehud Barak as saying.
Some media reports said that the ship was fired on by Israel.
However, the Israel Defense Forces said in a statement that, "No gunshots were fired on board during the boarding and capturing of the cargo boat."
The statement stressed that "any organization or country that wishes to transfer humanitarian aid to the Gaza Strip can do so via the established crossings between Israel and the Gaza Strip with prior coordination."
Israel's Operation Cast Lead, which ended in mid-January, killed some 1,300 Palestinians in Gaza and injured over 5,300 others. Up to 50,000 people were also left homeless in the Hamas-controlled enclave of 1.5 million.