Saif Abu Kheshek and Thiago Avila are the only activists from the April 2026 Gaza Sumud Flotilla to be held in Israel [Getty]
Israeli authorities are threatening detained Gaza flotilla activists with death, human rights groups have said on Monday, as Saif Abu Kheshek and Thiago Avila enter their sixth day in Israeli detention.
Adalah, the legal centre for Arab minority rights in Israel, said Brazilian national Avila had been explicitly threatened with death and “over 100 years in prison”, after two of its lawyers visited the activists while in prison.
Adalah said both Avila and Abu Keshek had been subjected to various forms of abuse and torture in jail. Their cells are being kept under constant high-intensity lighting, 24 hours a day and in cold temperatures.
The activists are also being kept in solidarity confinement and are being blindfolded when being moved outside of their prison cell and during medical examinations. The latter being “a gross violation of medical ethical standards,” Adalah said in a statement sent to The New Arab.
Lawyers from the organisation are now waiting to see whether the state of Israel will “file an extension-of-detention” request on Tuesday, after Abu Keshek and Avila’s detentions were extended by two days on Sunday, following a court appearance in Ashkelon.
“We continue to demand their immediate, unconditional release and end these illegal proceedings,” the NGO said.
Abu Keshek, a Spanish national, and Brazilian Avila were the only two activists brought for questioning in Israel after they were detained in international waters near Greece last week.
Israeli forces intercepted their vessels and abducted around 175 activists, who were mostly taken to the southeast European country.
Abu Keshek’s feet were in shackles, while Alvira had his hands tied behind his back during their court appearance on Sunday. Both activists also appeared exhausted, and with visible signs of torture, including scratches and bruises across their faces.
Adalah confirmed that Avila and Abu Keshek were subjected to “severe physical abuse amounting to torture, including being beaten and held in isolation and blindfolded for days at sea”.
So who are the two activists?
Saif Abu Keshek is a dual Spanish and Swedish national of Palestinian origin, and has been organising pro-Palestinian movements for over twenty years.
According to the Global Sumud Flotilla website, Abu Keshek, who is based in Barcelona, was a lead organiser in the Global March to Gaza and currently chairs the Global Coalition Against the Occupation in Palestine, and represents the Intersindical Alternativa de Catalunya (IAC), an independentist trade union based in the Spanish autonomous community.
He also sits on the board of the European Trade Union Network for Justice in Palestine.
In detention, Abu Keshek was “being kept hand-tied and blindfolded, and being forced to lie face-down on the floor from the moment of his seizure until this morning, resulting in bruising to his face and hands”, Adalah said over the weekend.
On Sunday, the Spanish foreign ministry demanded Abu Keshek’s “immediate release,” who he said was being “held illegally” by Israel following the interception of the Gaza-bound flotilla.
A foreign ministry spokesperson told the UK’s Guardian newspaper that the Spanish consul in Tel Aviv attended Abu Keshek’s court hearing in Ashkelon.
Thiago Avila, a seasoned climate and human rights activist from Brazil, had already participated in the Gaza Freedom Flotilla in June 2025, when he was aboard the Madleen vessel alongside high-profile activists, including Swedish activist Greta Thunberg, French Al Jazeera journalist Omar Faiad, and French-Palestinian MEP Rima Hassan.
Like his fellow activists, Avila was put in solitary confinement in Israel’s Ayalon Prison for several days after he was detained during the Freedom Flotilla mission.
The Brazilian activist had refused to sign deportation papers imposed by Israeli authorities at the time of his detention. Like he is doing now, Avila observed a dry hunger strike in Israeli custody in protest against his abduction and the conditions of his detention.
He also joined another Gaza-bound flotilla months later, joining the Global Sumud Flotilla, which set sail to the enclave between August and September 2025. Avila was detained from his vessel and also forcibly detained by Israeli authorities for the second time, before being forcibly expelled on 9 October to Brazil.
Boasting a following of 1.3 million followers on Instagram, Avila describes himself as an “organiser of collective actions sailing to break the illegal siege of Gaza and create a people’s humanitarian sea corridor”.
Over the years, Avila has strongly advocated for Palestinian territories and Lebanon in the face of Israeli wars and invasions, and has shown admiration for the likes of Leila Khaled, the famed Palestinian activist and former member of the Palestinian Liberation Organisation (PLO), as well as Hassan Nasrallah, the Hezbollah leader who was killed in an Israeli strike in Beirut in September 2024.
The Global Sumud Flotilla once again set sail towards Gaza in April in a bid to break the siege imposed by Israeli forces on the exhausted Gaza Strip, where Israel has waged a war for over two and a half years, killing over 72,500 Palestinians and subjecting them to starvation campaigns.
Israel controls all entry points into Gaza, which has been under an Israeli blockade since 2007, later intensified amid the war.
The Global Sumud Flotilla’s first Mediterranean voyage to Gaza last year drew worldwide attention, before being intercepted by Israeli forces off the coasts of Egypt and Gaza.
