Anti-migrant protester Daniel Thomas has been arrested on suspicion of criminal damage with intent to endanger life.
Thomas, known to his supporters as Danny Tommo, was arrested on Wednesday, police said.
A Hampshire Police statement read: "A man has been arrested after a boat that had an emergency responder on board, was damaged in English Channel.
"We received a report of the incident on Tuesday evening.
"Last night (Wednesday 23 September), a 37-year-old man, of no fixed abode, was arrested on suspicion of destroying ships or fixed platforms or endangering their safety under Section 11 of the Aviation and Maritime Security Act 1990, criminal damage, criminal damage with intent to endanger life, and conduct endangering ships, structures or individuals under Section 58 of the Merchant Shipping Act 1995.
"He remains in custody at this time."
The arrest comes after Thomas posted a video online appearing to show himself slashing an inflatable boat with a knife.
In footage on YouTube, he appeared to shout "traitors" and use a knife to cut the side of the vessel that had allegedly been used by people smugglers to transport migrants in the Channel.
He could be seen slashing and stabbing the small boat after a member of a rescue crew had boarded to apparently take the vessel back to France.
Thomas, who founded the anti-migration group Patriot Platform, appears to have also filmed his own arrest on another video that was streamed on his channel last night.
The footage shows him getting out of a car, which looked to be blocked in by other vehicles, at a petrol station.
He can be heard asking police if he can use his phone to speak to his children.
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One officer is recorded saying: "The information that I've been given... is that you've been involved in criminal damage recklessly endangering someone's life."
Thomas then repeatedly said: "I understand."
Hundreds of activists gathered in Gosport on Tuesday after Thomas filmed himself going out to sea to try to intercept a dinghy carrying dozens of migrants.
Hampshire and Isle of Wight Constabulary said three people had been charged after they gathered at the marina where they thought the boat's passengers were due to arrive.
Six people were arrested by officers during the evening, the force said.
(c) Sky News 2026: Anti-migrant protester Danny Tommo arrested after boat with emergency worker on damaged in

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