The father of a New Zealander reportedly detained from a Gaza-bound flotilla intercepted by Israel says he spoke to his son last night.

Eighteen year old Samuel Leason posted a video online - pre-recorded in case of emergency.

His father, A.D Leason, says Samuel described a submarine circling the flotilla, and a blockade of military vessels ahead.

"We were comforted by the fact that the Israeli Defence Force has announced that they weren't going to attack vessels, sink them or shoot people in the water like they did on another occasion. So we took comfort from that."

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