The families denounced Netanyahu’s plan to expand military operations. Yehuda Cohen, the father of Nimrod Cohen, an Israeli soldier held hostage in Gaza, said from the boat that Netanyahu is prolonging the war to satisfy extremists in his government and to prevent it from collapsing.

Israel’s retaliatory offensive has killed more than 60,000 Palestinians, according to Gaza’s Health Ministry. Its count doesn’t distinguish between fighters and civilians. The ministry operates under the Hamas government. The U.N. and other international organizations see it as the most reliable source of data on casualties.

Prime Minister Benjamin Netanyahu said today that Israel intended to take control of all of Gaza. He described the move as an effort to “assure our security” and liberate both Israelis and Palestinians “from the awful terror of Hamas.