Israeli naval forces intercepted the majority of a Gaza-bound humanitarian flotilla on Tuesday in the eastern Mediterranean, as organizers reported mass boardings, detentions and a continued push by a smaller group of vessels toward the enclave despite repeated warnings from Israel.

The Global Sumud Flotilla said Israeli forces halted or boarded 41 of its 54 vessels during coordinated maritime operations it described as taking place in international waters.

The group said the remaining 10 boats continued sailing toward Gaza, with its nearest vessel, Sirius, positioned about 145 nautical miles from the coast earlier in the day before later reporting the convoy had closed to roughly 121 nautical miles.

Organizers said the fleet carried 426 participants from 39 countries, describing the voyage as a coordinated humanitarian mission aimed at delivering aid directly to Gaza. They said the vessels endured what they called sustained naval pressure for more than 20 hours, while maintaining course toward the enclave.

A later statement from the group said Israeli military vessels continued to approach and board boats at sea, adding that communications with parts of the convoy had been disrupted during the operation. It said the remaining vessels were "on high alert” but still advancing.

Israel’s foreign ministry said earlier this week that it would not permit any breach of what it described as a lawful naval blockade on Gaza, urging participants to change course and return. Israeli media, citing a security source, reported that more than 40 vessels had been seized and around 300 activists detained, though figures have not been independently confirmed.

The flotilla departed from Marmaris in southern Türkiye last Thursday in a renewed attempt to break the blockade, after previous efforts were also intercepted by Israeli forces in international waters. Earlier incidents included the seizure of vessels and the detention and later deportation of activists from multiple countries.

The latest confrontation prompted a sharp response from Turkish President Tayyip Erdoğan, who condemned the intervention in Ankara and described the activists as "voyagers of hope,” calling on the international community to respond to Israel’s actions.

The maritime standoff comes amid the broader conflict in Gaza, where humanitarian groups and local authorities report severe shortages of food, fuel and medical supplies, alongside ongoing military operations that have driven repeated displacement and widespread destruction.