It is "unacceptable" that Irish citizens who were taking part in an aid flotilla to Gaza have been detained by Israel, the Irish PM has said.

Dr Margaret Connolly, sister of Irish President Catherine Connolly, is one of the 12 citizens.

The flotilla organisers said 10 boats in a 60-vessel convoy were intercepted in international waters and boarded by Israeli forces on Monday morning.

Israel's Prime Minister Benjamin Netanyahu said the raid was "effectively neutralising a malicious plan designed to break the isolation we have imposed on Hamas terrorists in Gaza".

President Connolly, who is on a three-day visit to England, has said the incident was "quite upsetting" and while very proud of her sister, she was "very worried about her".

Taoiseach (Irish prime minister) Micheál Martin said people have a right to protest and take part in a mission to highlight the "shocking" humanitarian issue in Gaza.

"In the first instance, what happened is absolutely unacceptable and is wrong," the taoiseach said.

He said Ireland would be raising the issue at "European Union level".

Tánaiste (deputy prime minister) Simon Harris said his thoughts were with the president and other families whose loved ones have been detained.

"My heart goes out to President Connolly and her family, and indeed all of the families of those detained.

"What Israel has done is, in my view, illegal."

Harris said the detention was a breach of international law.

He said members of government, opposition and others have criticised Israel's actions in Gaza but "unfortunately Israel seems to ignore the condemnation of the international world".

"That's why I think it's important that we look at the actions that can be taken," he said.

The Global Sumud Flotilla said the activists on board were carrying food, baby formula and medical aid for Palestinians in Gaza, where living conditions are dire and most of the 2.1m population is displaced, despite the ceasefire agreed by Israel and Hamas last October.

The Israeli foreign ministry described Gaza as "flooded with aid", saying more than 1.5m tonnes of aid and thousands of tonnes of medical supplies had entered the territory over the past seven months.

The UN said last week that many displaced families in Gaza were still forced to shelter in overcrowded tents or severely damaged structures due to the absence of safer alternatives.

Access to basic services remained limited, with inconsistent availability of clean water and impaired waste management systems that could not meaningfully address public health concerns, including those linked to pests and rodents, it added.

The Gaza war was triggered by the Hamas-led attack on southern Israel on 7 October 2023, when about 1,200 people were killed and 251 others were taken hostage.

Israel responded by launching a military campaign in Gaza, during which more than 72,770 people have been killed, according to the territory's Hamas-run health ministry. (BBC)

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