Israeli forces opened fire on at least two vessels in an aid flotilla sailing towards Gaza on Tuesday, according to video footage and flotilla organisers, but Israel said no live ammunition was used and there were no casualties.

Video from the flotilla’s livestream showed soldiers firing shots at two of the boats. The type of ammunition fired was not clear.

“At no point was live ammunition fired,” the Israeli foreign ministry said in a statement.

“Following multiple warnings, non-lethal means were employed toward the vessel – not toward protesters – as a warning. No protesters were injured during this event,” it added, only referring to action against one vessel.

The Global Sumud Flotilla said on its website that 48 vessels had been intercepted, with some 400 people detained and two boats still sailing in the eastern Mediterranean.

Israel’s foreign ministry had said on X on Monday that it “will not allow any breach of the lawful naval blockade on Gaza”.

Ships from the Global Sumud Flotilla had set sail for a third time on Thursday from southern Turkey, after earlier attempts to deliver aid to Gaza were intercepted by Israel in international waters.

The group said previously there were 426 people taking part in the flotilla from 39 countries.

The United States Treasury said on Tuesday it was imposing sanctions against four people associated with what it described as the “pro-Hamas” flotilla.

Pro-Palestinian activists say Israel and the US wrongly conflate their advocacy for Palestinian rights with support for Hamas extremists.

Palestinians and international aid bodies say supplies reaching Gaza are still insufficient, despite a ceasefire agreed in October that included guarantees of increased aid. Reuters