(16:50 GMT) Thiago Avila, a Brazilian activist on board the Madleen vessel, tells Al Jazeera the boat is currently about 185km (100 nautical miles) off the coast of Gaza.

“We are here to support Gaza and demand an end to the bombing and starvation,” Avila said. “Despite threats, we will continue our journey. The world must stand with us.”

He said drones are flying overhead and communication systems had been jammed.

“We know Israeli forces are prepared to confront us with weapons, but we are not afraid,” he said. “What we face is nothing compared to what Palestinians in Gaza endure.”

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