Tunisian authorities have denied claims that one of the Gaza-bound vessels carrying aid and pro-Palestinian activists including Greta Thunberg was attacked by a drone.

The organisers of the flotilla, Global Sumud Flotilla (GSF), said that the Portuguese-flagged vessel had been struck by a drone while anchored outside the port of Sidi Bou Said in Tunisia. All six passengers and crew were safe, they added.

A spokesperson for Tunisia's national guard told the Agence France-Presse news agency that 'no drone' had been detected and the investigation was ongoing.

The humanitarian aid flotilla set sail from Barcelona last week, and arrived in Tunisia on Sunday.

The GSF said their 'Family boat' was struck in Tunisian waters, and fire had damaged the main deck.

In videos published to their Instagram, spokespeople for the GSF stated that an 'incendiary device' caused a fire onboard the vessel, which the crew was able to extinguish.

Tunisia's National Guard spokesman refuted reports of a drone attack, indicating that initial inspections suggested the explosion originated inside the vessel.

Francesca Albanese, a UN Human Rights Council special rapporteur and Tunisian resident, mentioned that if an attack could be verified, it would be seen as aggression against Tunisian sovereignty.

Albanese has been critical of Israel's military actions in Gaza and was recently sanctioned by the United States, a move that was supported by Israeli Prime Minister Benjamin Netanyahu.

The mission of the GSF aims to 'break Israel's illegal siege on Gaza', yet they have faced numerous challenges, including past incidents where Israeli forces intercepted their missions.

Previous claims of drone attacks on aid ships bound for Gaza have also been reported, escalating tensions in the volatile region.

Last month, the UN announced there was famine in Gaza, attributing it to Israel's obstructive actions regarding aid, which Israel contests.

As the conflict continues, the humanitarian needs in the region remain critically high.