Two activists who participated in a Gaza-bound aid flotilla have been brought to Israel for questioning, the foreign ministry said Saturday, after the vessels were intercepted by Israeli forces.

The flotilla of more than 50 vessels had set sail from ports in France, Spain and Italy with the aim of breaking an Israeli blockade of Gaza and bringing supplies to the devastated Palestinian territory.

They were intercepted by Israeli forces in international waters off Greece early on Thursday.

Israel said it had removed around 175 activists from the flotilla, but organisers accused Israeli personnel of ‘kidnapping’ 211 people.

Two of them, Saif Abu Keshek from Spain and Thiago Avila, a Brazilian, were taken to Israel ‘for questioning by law enforcement authorities’, the foreign ministry said on X.

Spanish foreign minister Jose Manuel Albares denounced Israel’s detention of Abu Keshek as ‘illegal’, warning it came at a moment of already deteriorating ties between the two countries.

‘We are facing an illegal detention in international waters, outside any jurisdiction of the Israeli authorities so Saif Abu Keshek must be released immediately so that he can return to Spain,’ Albares told Rac1 radio.

‘This is an episode that further strains our relationship...[with Israel] because of how unacceptable this situation is, because a state does not conduct itself in this manner.’

Ties between Israel and Spain have nosedived since the Gaza war sparked by the October 2023 Hamas cross-border attacks, with Israel angered by prime minister Pedro Sanchez’s unrelenting criticism of its bombardment of the Palestinian territory.

Both countries have withdrawn their ambassadors.

Israel’s foreign ministry said the two activists were affiliated with an organisation that was sanctioned by the US Treasury.

That group—the Popular Conference for Palestinians Abroad -- has been accused by Washington of ‘clandestinely acting on behalf of’ Palestinian militant group Hamas.

The treasury said the organisation had played a role in organising other Gaza-bound flotillas aimed at breaking Israel’s blockade.

Israel’s foreign ministry said Abu Keshek was a leading member of the PCPA. It said Avila was also linked to the organisation and was ‘suspected of illegal activity’.

‘Both will receive a consular visit from the representatives of their respective countries in Israel,’ the ministry said.

Albares rejected the allegation, saying: ‘The information I myself have requested indicates that no link can be established between Saif Abu Keshek and Hamas’.

Avila was among the organisers of a flotilla that tried to bring aid to Gaza last year. That effort was also intercepted by Israeli forces.

Israel controls all entry points into Gaza and the territory has been under Israeli blockade since 2007.

Throughout the Gaza war, there have been shortages of critical supplies in the Palestinian territory, with Israel at times cutting off aid entirely.

Organisers of the latest flotilla said the Israeli interception took place more than 1,000 kilometres from Gaza.

They said their equipment was smashed and the intervention left them facing a ‘calculated death trap at sea’.

Dozens of intercepted activists disembarked on Friday at the Greek island of Crete, according to an AFP journalist.

Organisers published photos on X showing two activists with bruises on their faces, while one participant said in footage that Israeli forces had ‘beaten’ them ‘several times’.

Hamas condemned the interception, urging rights groups to pursue legal action against Israeli authorities for ‘crimes against the Global Sumud Flotilla, ensuring they do not enjoy impunity’.

The Global Sumud Flotilla’s first Mediterranean voyage to Gaza in the summer and autumn of 2025 drew worldwide attention, before Israeli forces intercepted the boats off the coasts of Egypt and Gaza in early October.

Crew members, including Swedish activist Greta Thunberg, were arrested and expelled by Israeli forces.