PARIS 

Israel was accused of “state piracy” after its navy boarded an activist ship seeking to challenge the naval blockade of Gaza on Monday.

Four boats carrying pro-Palestinian activists had been trying to reach Gaza when one, the Marianne of Gothenburg, was boarded and escorted to the Israeli port of Ashdod.

The France-Palestine Solidarity Association said those aboard had been “kidnapped” after the ship was “hijacked” and forced to head to Israel.

"It is a new act of piracy… Israel has no sovereignty over international waters off Gaza," the group said in a statement.

The Freedom Flotilla Coalition said the Marianne had been surrounded by three Israeli naval vessels in the early hours of Monday morning while sailing in international waters off the coast of Gaza.

According to an Israeli statement, the ship was boarded without the use of force.

Israel claimed it had "exhausted diplomatic channels" in an attempt to head off the flotilla before taking action.

In a statement, Prime Minister Benjamin Netanyahu described the flotilla as "a demonstration of hypocrisy" that amounted to support for Hamas, the group that controls Gaza and has been in conflict with Israel for decades.

He claimed the interception of the Marianne was in accordance with international law and even received UN support.

But the coalition said it had “no reason to believe that Marianne’s capture was ‘uneventful’”, pointing out that 10 people were killed aboard the Mavi Mamara in 2010 when Israeli commandos boarded the vessel and that three years ago those aboard the Estelle were “badly  tasered and beaten with clubs.”

“Israel's repeated acts of state piracy in international waters are worrying signs that the occupation and blockade policy extends to the entire eastern Mediterranean” the coalition added in its statement.

“We demand that the Israeli government cease and desist the illegal detainment of peaceful civilians travelling in international waters in support of humanitarian aid.”

UN Secretary General Ban Ki-moon’s deputy spokesman Farhan Haq welcomed the "peaceful completion" of the confrontation.

He told an Anadolu Agency correspondent in New York the secretary general’s office was seeking further details from UN officials in the region.

The Marianne is part of the Third Freedom Flotilla to Gaza. It had stopped in Greece, Spain and France on its way to Gaza.