A retired Canadian politician is in custody after the ship he was on attempted to break through Israel's blockade of Gaza Saturday.

Jim Manly, a former NDP MP, was one of about 30 people from eight countries on board the Swedish-owned Estelle. The ship was stopped by six Israeli naval vessels and ordered to sail to the southern Israeli port of Ashdod.

All the occupants are expected to be deported over the next two days.

Israel imposed a naval blockade on Gaza in 2009, saying it was needed to prevent the smuggling of arms to the militant group Hamas which governs the Palestinian enclave. It eased the blockade a year later after it was criticized by the international community for killing nine activists who were trying to break the siege.

In a statement issued Saturday, Israeli Prime Minister Benjamin Netanyahu praised the military for enforcing the blockade.

He said there "is no humanitarian crisis in Gaza" and accused the activists of trying to "to provoke and slander Israel's name."

In a column that appeared on straight.com, 79-year-old Manly's wife, Eva, said her husband is on the Estelle "out of a commitment to human rights and social justice. He is there in the hope that his action will bring awareness to his fellow Canadians about what is being done to the Palestinians in the name of Israeli security.

"He is there in the hope that his actions may bring Canadian members of Parliament from all parties, but especially the NDP, the 'party of conscience.'"