Mosab Hassan Yousef, the son of a senior Hamas leader who later became an Israeli intelligence asset, has called on Israelis to mount a counter-flotilla in response to an international effort to break the blockade of Gaza.

Yousef, who once worked undercover for the Israel Security Agency (Shin Bet) has since become a vocal advocate for Israel abroad, issued his appeal over the weekend in a series of fiery social media posts.

“Listen up, Israeli boat owners—sea wolves, fathers, mothers, sons, daughters,” he wrote. “Fifty boats draped in fake flags, packed with terrorist sympathizers, sail to slander us while our hostages rot. This isn’t a protest; it’s a thunderclap. We don’t debate. We sail.”