A freedom flotilla sailing to break the blockade of Gaza was captured early Monday morning by the Israeli navy and the 18 journalists, campaigners, and crew aboard are currently in the occupying army's custody, in an attack global supporters are calling piracy and kidnapping at high sea.

David Heap, spokesperson for the international Freedom Flotilla Coalition, told Common Dreams that supporters lost contact with the ship—the Marianne of Gothenburg—at approximately 5:00 AM Gaza time when it was roughly 100 nautical miles from the strip. The coalition still has not spoken with any of the people detained and does not have any information about their well-being.

Israeli authorities claimed they intercepted the vessel without incident, but the global coalition says there is reason to be skeptical of this claim.

"We have no reason to believe that Marianne’s capture was 'uneventful,' because the last time the IDF said something like that, in 2012, the people on board the 'Estelle' were badly tasered and beaten with clubs," said the coalition in a statement released Monday. "Back in 2010, ten passengers of Mavi Marmara were murdered by the IDF during a similar operation in international waters."

Whatever the details of the seizure, Heap emphasized that "it's an act of kidnapping to take international citizens from international waters to a country not of their choice against their will." The Israeli military's action, moreover, raises concerns that "the occupation and blockade policy extends to the entire eastern Mediterranean," the coalition said.

The Marianne originated in Sweden but carried people from around the world, including Tunisia, Spain, Morocco, and New Zealand. It was part of a global effort, under the banner of Freedom Flotilla III, that embarked from Greek ports Saturday in an effort to break the Israeli siege of Gaza—which is politically and financially backed by the United States and enabled by the active participation of Egypt.

In addition to the Marianne, the initiative included the supporting vessels Rachel, Vittorio, and Juliano II, and altogether the vessels carried 47 people from 17 countries.

"While the Flotilla bears much-needed aid, our main cargo is, as always, human solidarity and non-violent direct action for the respect of human rights," said Freedom Flotilla III in a statement.

The effort was supported by people around the world and followed numerous other attempts to sail against the siege of Gaza, in solidarity with the 1.8 million people living there—roughly half of whom are children. One of the most densely populated places on earth, Gaza faces an escalating humanitarian crisis due to the blockade, which has made it nearly impossible to rebuild destroyed infrastructure—from hospitals to refugee shelters to schools—after Israel's 50-day military assault last summer.

"While our attention is on our friends and colleagues on the boats, our goal is to stand with our civil society partners in Gaza," said Heap. "Our purpose is to bring the attention of the world to the inhumane blockade. Our thoughts are with the people waiting for us on the shore and waiting for the world to demand the end to this blockade."

The three boats accompanying the Marianne have turned around and are now en route to Greek ports. But Heap emphasized that this development is just temporary: "We will sail again."