One of the Gaza-bound vessels carrying aid and pro-Palestinian activists including Greta Thunberg was struck by a drone, the flotilla organisers have claimed.
The Global Sumud Flotilla (GSF) posted footage on Instagram that appeared to show the Portuguese-flagged vessel being hit by an object, stating that all six passengers and crew were safe after the incident outside the Tunisian port of Sidi Bou Said.
Tunisian authorities quoted by Reuters stated that reports of drone involvement had 'no basis in truth', claiming an initial inspection indicated the explosion originated inside the vessel.
The humanitarian aid flotilla had set sail from Barcelona the previous week and arrived in Tunisia on Sunday.
The GSF asserted their 'Family boat' was struck in Tunisian waters, with fire damaging the main deck.
In a series of videos published to their Instagram, GSF spokespeople stated that an 'incendiary device' triggered a fire onboard the vessel, which crew members managed to extinguish.
A spokesperson for the Tunisian national guard confirmed to AFP that 'no drone' had been detected and that the investigation was ongoing.
BBC Verify has authenticated several videos showing a claimed strike on the 'Family' vessel off the coast of Tunisia.
David Heathcote, Head of Intelligence at McKenzie Intelligence Services, noted the nature of the impact indicates the object may have been dropped from a drone. He emphasized that the footage challenges the Tunisian authorities' account of the event.
United Nations Human Rights Council special rapporteur, Francesca Albanese, who was aboard the vessel, stressed that if verified, the incident would represent an 'assault and aggression against Tunisia, and Tunisian sovereignty'.
Albanese, a critic of Israel's military actions in Gaza, has faced US sanctions that Israeli Prime Minister Benjamin Netanyahu welcomed as a measure against a smear campaign.
The flotilla aims to 'break Israel's illegal siege on Gaza' but has faced multiple setbacks this year. Israeli forces previously boarded a boat carrying humanitarian aid, detaining the activists onboard.
Past accusations of drone attacks on aid ships to Gaza have surfaced, as with the Freedom Flotilla claiming its vessel was struck in May.
Recent reports by a UN-backed body confirmed famine conditions in Gaza, a claim Israel contested, asserting no starvation exists.
The situation continues to evolve amid a backdrop of escalating tensions and humanitarian crises in the region.
