STOCKHOLM - Seven Swedish activists detained by Israel’s navy for attempting to breach its blockade of Gaza have been deported to Sweden, the organisers of the Ship to Gaza activist flotilla said Wednesday.

Four of the activists arrived back in the Scandinavian country on Wednesday, and the three others were expected later in the day, Ship to Gaza Sweden spokesman Dror Feiler told AFP.

The Israeli navy said it intercepted the ship, Freedom for Gaza, late Friday “in accordance with international law”, and took it to the port of Ashdod. The ship was carrying medical supplies and had a total of 12 crew and activists on board, hailing from Sweden, Spain, Canada and Germany and France. All have been deported, Feiler said.

Meanwhile, Swedish Foreign Minister Margot Wallstrom said Wednesday Israel’s interception and boarding of the ship, as well as the detention of the activists and crew, violated international law.

“The (Swedish) government has been in contact with Israeli authorities about Ship to Gaza and has insisted that the actions of the Israeli authorities regarding the Swedish-flagged vessel Freedom and the people on board are not backed up by international law,” Wallstrom said in a statement.

She said her government had also demanded that the ship and its cargo be released.

The Gaza Strip has been under Israeli blockade for more than a decade, with Israel saying it is necessary to prevent the Palestinian enclave’s militant Hamas rulers from obtaining weapons.

Israel has defended the legality of Friday’s seizure, recalling that a 2011 UN report found its naval blockade on Gaza was legal.

Freedom was the second boat of the “Freedom Flotilla” to be intercepted en route to “break the blockade” on Gaza, organisers said.

Four boats left Scandinavia in mid-May and stopped in some 28 ports along the way, with two remaining behind after a recent stop in the Italian port of Palermo.

On Sunday, the Israeli navy intercepted a Norwegian-flagged activist boat that was part of the flotilla.

Israel has fought three wars with Palestinian militants in Gaza since 2008 and says the blockade is necessary to keep them from obtaining weapons or material that could be used for military purposes.

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UN officials have called for the blockade to be lifted, citing deteriorating humanitarian conditions in the Palestinian enclave run by Islamist movement Hamas and where 80 percent of the two million population are dependent on aid.