Israeli sailors intercepted a small boat carrying former Tunisian President Moncef Marzouki and 17 other activists sailing to Gaza to protest Israel's blockade, the government said Monday morning.

The boat — the Marianne av Göteborg, one of four in a convoy called Freedom Flotilla III carrying pro-Palestinian activists — was boarded and redirected to the port of Ashdod without incident, the Israeli Defense Forces said in a one-paragraph statement.

"This flotilla is nothing but a demonstration of hypocrisy and lies that is only assisting the Hamas terrorist organization and ignores all of the horrors in our region," Prime Minister Benjamin Netanyahu said. "We are not prepared to accept the entry of war materiel to the terrorist organizations in Gaza as has been done by sea in the past."

Before the confrontation, Israeli Prime Minister Benjamin Netanyahu's office sent a mocking letter to the estimated 50 activists on the four boats, saying: "Welcome to Israel. You seem to have gotten lost. Perhaps you meant to set sail for a place not far from here — Syria. There the Assad regime is slaughtering its own people every day with the support of the murderous regime in Iran."

The activists, who stressed that they were a nonviolent group, confirmed the interception Monday morning on Twitter.

Israeli occupied forces intercepted Marianne. The boat is currently en route to Ashdod port #SOSFreedomFlotilla pic.twitter.com/bqDOzcR7h1 — Freedom Flotilla (@GazaFFlotilla) June 29, 2015

"We call once again on the government of Israel to finally lift the blockade on Gaza and let the peaceful ship, the 'Marianne', reach its destination in order to deliver its cargo of dignity and hope," Freedom Flotilla III said in a statement.