Independent TD Barry Heneghan and author Naoise Dolan are among five Irish citizens detained by the Israeli defence forces, after a number of flotilla vessels heading to Gaza were intercepted overnight.
Ms Dolan is the author of two books and a columnist for The Guardian newspaper and other publications.
Another Irish citizen, Dr Veronica O'Keane, a consultant psychiatrist, was on the Conscience.
The organisers of the Gaza-bound aid flotilla said the Israeli army intercepted at least three of its boats.
The Milad is listed as having been intercepted on a tracker website associated with the campaign.
The Department of Foreign Affairs has said it is looking into the reports.
Tánaiste and Minister for Foreign Affairs Simon Harris said his priority is the safety of the Irish citizens and the Irish Embassy in Tel Aviv "is in contact with Israeli authorities regarding next steps".
He said he expects the detainees will be transferred to Ashdod port for processing, before being taken to a detention facility near Tel Aviv, where, he said, the embassy team will visit them as soon as possible.
Mr Harris added that he is due to receive an update from Ireland's Ambassador to Israel Sonya McGuinness.
The Global Sumud Flotilla said on X earlier that: "Three vessels - Gaza Sunbirds, Alaa Al-Najjar, and Anas Al-Sharif - have been attacked and illegally intercepted by the Israeli military" in the early morning, 220km off the coast of Gaza.
🆘The Milad crew are being illegally abducted by Israel
— Global Sumud Flotilla (@GlobalSumud) October 8, 2025
While it was sailing, in peace, in accordance with international law, outside Israeli jurisdiction. We call on all our governments and people to condemn this crime and to demand the immediate release of all abducted crew,… pic.twitter.com/di1pxaqvCy
It said another ship, the Conscience, carrying more than 90 journalists, doctors and activists, was also "under attack", while its crew on the Milad "are being illegally abducted by Israel".
The Israeli foreign ministry confirmed it had intercepted boats entering waters it says fall under its blockade of the war-torn Palestinian territory.
"Another futile attempt to breach the legal naval blockade and enter a combat zone ended in nothing. The vessels and the passengers are transferred to an Israeli port," it said on social media.
"All the passengers are safe and in good health. The passengers are expected to be deported promptly," it added.
Sinn Féin Spokesperson on Foreign Affairs Donnchadh Ó Laoghaire TD has called on the Government to intervene urgently to safeguard the welfare and safety of Irish citizens detained by Israel.
"The illegal abduction of Irish citizens, on a peaceful humanitarian mission to bring aid to Gaza, is utterly unacceptable.
"Once again, Israel has totally disregarded International Law, by abducting these citizens, including Deputy Barry Heneghan, and many others from across the world," he said.
"The Global Sumud Flotilla is a peaceful mission to bring aid to a beleaguered civilian population, that has been systematically denied aid by the policies of the Israeli Government. These Irish citizens are acting on a humanitarian mission and their abduction is totally unjustified."
Last week Israeli naval forces stopped another Global Sumud Flotilla of around 45 vessels, carrying politicians and activists including Swedish climate campaigner Greta Thunberg.
Fifteen Irish citizens were also detained by Israel. Most of them have returned to Ireland.
Sinn Féin Senator Chris Andrews returned to Dublin Airport this morning after having spent several days in an Israeli jail.
It appears that the vessel carrying Indep TD Barry Heneghan towards Gaza has been intercepted by the Israel Defence Forces. Meanwhile, SF Senator Chris Andrews returned to Dublin Airport early this morning, after being released from an Israeli jail. @rtenews pic.twitter.com/xM9kOZNBXk
— Paul Cunningham (@RTENewsPaulC) October 8, 2025
Speaking after arriving at Dublin Airport yesterday afternoon, Irish activists described aggressive behaviour from the IDF, a disregard for medical support and a lack of basic sanitary facilities.
Tadhg Hickey said the treatment of those who were on the Flotilla was "inhumane", while Patrick O'Donovan said the IDF were very aggressive and violent when they were first arrested.
"And then we were brought ashore and we were tied with tie wraps behind our back, our arms, behind our back at the port, and we were left there for about six hours on the ground," he added.
Additional reporting AFP
