JERUSALEM (JTA) — A flotilla of 40 boats from Gaza was turned back by the Israeli Navy on Saturday as they attempted to breach the Israeli blockade of the Hamas-run coastal territory and sail into Israeli waters. The small fleet was part of the larger “March of Return” campaign linked to more than a month of violent riots on the Gaza border earlier this summer. More than a hundred Palestinians were killed over six weeks of clashes with Israeli forces.

“The flotilla represents a message to the Palestinian factions involved in the peace agreement negotiations—we will not agree to any solution that will not lead to the lifting of Gaza blockade,” the organizers of the flotilla said in a statement reported by Israeli news website Ynet.

The Palestinian boats turned back after Israeli forces fired warning shots in their direction.

Late last month the Israeli Navy intercepted a ship attempting to breach its blockade of Gaza. The motor vessel, named Al Awda, or The Return, was contacted by Israel’s Navy about 49 nautical miles from the port at Gaza City in international waters and warned to stop or prepare to be boarded, the Freedom Flotilla Coalition said on its website.

Al Awda was sailing under a Norwegian flag, carrying 22 people and a cargo of medical supplies, according to the website. There were people from 16 nations on board, including human rights supporters, journalists and crew, along with about $15,000 worth of medical supplies. The boat, a former fishing vessel from Norway, was a gift to Palestinian fishers in Gaza, according to the website.

Tensions between Hamas and Israel have risen significantly in recent days, with the Islamic terrorist group firing hundreds of projectiles into Israeli territory and the Israelis carrying out retaliatory strikes against Hamas outposts and fighters. Despite a tense ceasefire, clashes on the border have continued, with three Palestinians killed on Friday.