Eight Palestine Action activists on hunger strike in the UK while in prison awaiting trial are dying, according to a doctor.
Dr James Smith, a qualified emergency physician who is a lecturer at University College London, said the group, who are accused of break-ins or criminal damage on behalf of Palestine Action, need specialist medical help.
His warning comes amid calls for the UK government to intervene from doctors and politicians, including former Labour leader Jeremy Corbyn, who claimed there have been "regular breaches of prison conditions and prison rules".
Some of the eight prisoners, who began the action in protest at being held in custody while awaiting trial, have been taken to hospital.
At a press conference in south London, Dr Smith told journalists: "The hunger strikers are dying.
"We are alarmed by accounts of substandard monitoring and treatment within the prison system.
"Last week more than 200 members of the British Medical Association wrote to the BMA to sound the alarm."
Dr Smith added: "It is my view, as an NHS doctor, that the complexity of the hunger strikers' care needs must now be managed with regular specialist input if not continuous monitoring in hospital."
Yesterday, one of the hunger strikers, Qesser Zuhrah, was transported to hospital from HMP Bronzefield prison, following calls from protesters for medical intervention.
Ms Zuhrah was on day 46 of her hunger strike when she was taken by ambulance to hospital.
Your Party MP Zarah Sultana said today that Ms Zuhrah's family has confirmed she is safe and is continuing her hunger strike.
Almost 900 health professionals have written to UK Deputy Prime Minister and Justice Secretary David Lammy, Health Secretary Wes Streeting, senior NHS officials and senior prison officials to express the same demand.
UK Prime Minister Keir Starmer has previously said the "rules and procedures" are being followed, after facing questions in the House of Commons about why his ministers had refused to meet with representatives of those striking.
But Rahma Hoxha, the sister of Teuta Hoxha, who is on day 40 of a hunger strike in prison, said: "The longer this goes on the scarier this gets for her and my family, my sister shouldn’t even be in prison.
"The prison guards called her a terrorist, even though she’s on remand.
"She said it feels as if the government is trying to bury them alive and for them to go quietly."
Shahmina Alam, the sister of Kamran Ahmed, who is on day 39 of his hunger strike, told reporters: "Our family have never felt this much anxiety, never dreaded phone calls as much as we have now.
"His heart is giving in and his pulse is slowing down, he is losing half a kilogram every day."
She added: "The justice system is hanging on a very thin thread."
McDonald calls on Starmer to engage directly
Meanwhile, Sinn Féin leader Mary Lou McDonald said she has written to Mr Starmer to express "serious concern" regarding the "life-threatening situation" facing six of the hunger strikers.
Ms McDonald said the situation represents "a serious humanitarian crisis".
"Urgent action is needed and I have urged the British Prime Minister to engage directly to find an immediate resolution to this protest."The right to a fair and timely trial, including access to reasonable bail, is fundamental in any democratic society and must be upheld without exception," Ms McDonald said.
Earlier this week, a group of 51 MPs and peers, including 19 Labour MPs, wrote to Mr Lammy urging him to meet the lawyers of the eight prisoners.
Labour MPs Rachael Maskell, Bell Ribeiro-Addy, Paula Barker, Mary Kelly Foy and Simon Opher were among the signatories to the letter.
MPs Jeremy Corbyn and John McDonnell were also at the press conference along with other representatives of the activists.
Mr Corbyn called on Mr Lammy to "do what your job requires you to do, uphold the prison regulations and make contact with the representatives of the hunger strikers in order to save life. It is in your hands".
The eight prisoners on hunger strike are facing charges related to alleged break-ins or criminal damage on behalf of Palestine Action before the group was banned under terrorism legislation - charges which they deny and have called to be dropped.
Four of the group are accused of playing roles in the break-in to an Israeli-linked defence firm in 2024 and are due to go on trial in May next year at the earliest.
The other four are accused of breaking into RAF Brize Norton in June, where it is alleged they caused millions of pounds worth of damage to two military jets.
Responding to the issue, prisons minister James Timpson said the service is "very experienced" at dealing with hunger strikes.
"Unfortunately, over the last five years we have averaged over 200 hunger strike incidents every year and the processes that we have are well-established and they work very well - with prisons working alongside our NHS partners every day, making sure our systems are robust and working - and they are," he said.
"I am very clear. I don’t treat any prisoners differently to others. That is why we will not be meeting any prisoners or their representatives."