Six of eight activists who remain in detention in Israel after their boat was intercepted on its way to try to break Israel’s naval blockade of Gaza are expected to be deported within hours, a human rights group has said.

“After more than 72 hours in Israeli custody following the unlawful interception of the Madleen Freedom Flotilla in international waters… six volunteers are now being transferred to Ben Gurion Airport for deportation,” Israeli rights group Adalah, who provided legal advice to the activists, said.

Adalah said two other activists remain in Israeli custody awaiting deportation on Friday.

The BBC has approached the Israeli foreign ministry for comment.

The deportation of the six is expected to happen on Thursday or early on Friday, Adalah said.

Among those expected to be deported is Rima Hassan, a French-Palestinian member of the European Parliament.

A post on her X account said Hassan had left prison and was inviting people to meet in Paris’ Place de la République at 21:00 (20:00 BST).

The other five activists are said to be Mark van Rennes from the Netherlands, Suayb Ordu from Turkey, Yasemin Acar from Germany, Thiago Avila from Brazil, and Reva Viard from France.

Adalah said the two others yet to be deported are Pascal Maurieras and Yanis Mhamdi, both French nationals. It said they were still in custody in Givon prison and were expected to be deported on Friday afternoon.

In a statement, Adalah said: “While in custody, volunteers were subjected to mistreatment, punitive measures, and aggressive treatment, and two volunteers were held for some period of time in solitary confinement.”

It added: “Adalah calls for the immediate release of all eight volunteers and for their safe passage to their home countries. Their continued detention and forced deportation are unlawful and a part of Israel’s ongoing violations of international law.”

The Israeli foreign ministry previously said those who refused to sign deportation documents would face judicial proceedings to have them deported, in accordance with Israeli law.

A group of 12 people had been sailing on the yacht Madleen when it was intercepted by Israeli authorities on Monday, about 185km (115 miles) west of Gaza.

The expedition, organised by the Freedom Flotilla Coalition (FFC), had been aiming to deliver a “symbolic” amount of aid to Gaza in defiance of Israel’s blockade and to highlight the humanitarian crisis there.

At the time, the Israeli foreign ministry dismissed it as a “selfie yacht” carrying “less than a single truckload of aid”.

Following the activists’ detention, four, including Swedish activist Greta Thunberg and two French nationals, agreed to be deported immediately.

Upon her arrival in France, Thunberg accused Israeli authorities of kidnapping her and other activists on the boat while they were in international waters.

Israel’s foreign ministry said unauthorised attempts to breach its blockade of Gaza were “dangerous, unlawful, and undermine ongoing humanitarian efforts”.

It added that the aid transported on the FFC boat, which included baby formula and medicine, would be transferred to Gaza “through real humanitarian channels”.

Israel stopped all deliveries of humanitarian aid and commercial supplies to Gaza on 2 March and resumed its military offensive two weeks later, collapsing a two-month ceasefire with Hamas.

It said the steps were meant to put pressure on the group to release the hostages still held in Gaza, but the UN warned that Gaza’s 2.1 million population were facing catastrophic levels of hunger because of the resulting shortages of food.

Three weeks ago, Israel launched an expanded offensive to take control of all areas of Gaza. It also partially eased the blockade, allowing in a “basic” amount of food.

Israel is now prioritising distribution through the Gaza Humanitarian Foundation, which it backs along with the US. The UN and other aid groups are refusing to co-operate with the new system, saying it contravenes the humanitarian principles of neutrality, impartiality, and independence.

It has been 20 months since Israel launched a military campaign in Gaza in response to the Hamas-led cross-border attack on Israel on 7 October 2023, in which about 1,200 people were killed and 251 others were taken hostage.

At least 55,207 people have been killed in Gaza since then, according to the territory’s Hamas-run health ministry.