JERUSALEM – A defiant Israel enforced its three-year-old blockade of Hamas-ruled Gaza on Saturday, with naval commandos swiftly commandeering a Gaza-bound aid vessel carrying an Irish Nobel laureate and other activists and forcing it to head to an Israeli port instead.

The bloodless takeover stood in marked contrast to a deadly raid of another Gaza aid ship last week. However, it was unlikely to halt snowballing international outrage and demands that Israel lift or at least loosen the devastating closure that confines 1.5 million Palestinians to a small sliver of land and allows in only basic humanitarian goods.

For now, the confrontations at sea are likely to continue.

The organizers of Saturday’s sail said they planned to dispatch as many as three more ships in coming months and that four captains already have volunteered for the missions.

“What Israel needs to understand is that nothing is accomplished with force,” said Greta Berlin of the Cyprus-based Free Gaza group, which sent the latest aid vessel, the Rachel Corrie.

Israel said it would block any attempt to reach Gaza by sea, in order to prevent weapons from reaching the Iranian-backed Islamic militant group. “Israel will not allow the establishment of an Iranian port in Gaza,” Prime Minister Benjamin Netanyahu said.

At the same time, Israel signaled Saturday it is considering easing the blockade, although officials provided no details. Israel and Egypt closed Gaza’s borders after Hamas seized the territory three years ago from Western-backed Palestinian President Mahmoud Abbas.

Saturday’s takeover of the 1,200-ton ship was over in minutes.

After trailing the vessel for six hours across the Mediterranean, Israeli commandos boarded it from speed boats around noon, in international waters about 20 miles from Gaza, and forced it to sail to the Israeli port of Ashdod.

Footage from an Israeli aircraft showed the passengers sitting quietly in two rows on the top deck. A man described by the Israeli military as the captain got up, raised his arms and walked toward the soldiers.

The military said the crew of the Rachel Corrie dropped down one of the ship’s ladders to make it easier for the forces to board.

The activists could not be reached to describe the events because communication with the ship was cut during the operation. Berlin called the takeover an outrage.

The 11 passengers and eight crew members will be deported, although those who object will be detained and given a chance to appeal, officials said.

Those aboard included Mairead Corrigan, who won the 1976 Nobel Peace Prize for her work with Catholics and Protestants in Northern Ireland, and the former U.N. humanitarian coordinator in Iraq, Denis Halliday.

Sabine Haddad, spokeswoman for the Israeli Interior Ministry, said that all 19 were being held at Israel’s international airport Saturday night, and that eight agreed to leave voluntarily today.

The remaining activists, including Corrigan and Halliday, were challenging the deportations, though Haddad said she expected some of them to change their mind and leave voluntarily.