In Iran, the climate of fear has been restored after the clerics who run this country successfully crushed nationwide revolt.
Yet their determination to stay in power is matched by their efforts to conceal what has happened.
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Iran's communications blackout - which began on 8 January - has eased somewhat, with sporadic internet access now possible.
But it remains difficult to communicate with people inside the country, who must find both the courage and the practical means to reach out.
The activist doctor
Dr Yaser Rahmani-Rad wants his voice to be heard. A specialist in internal medicine at a public hospital in Tehran, he told Sky News what he saw as the regime launched its crackdown in the capital.
"Pressure was being put on nurses and doctors to clear out the emergency department. In other words, any patient who was there - whether they had clear medical indications or not - was told to be discharged. They wanted the emergency ward emptied for security forces who had been injured."
We know members of the Iranian security forces have made incursions into clinics and hospitals. Images of one such operation inside the Imam Khomeini Hospital in western Iran have been posted online.
Staff members are seen trying to stop them at the front entrance.
Dr Rahmani-Rad relayed details passed to him by colleagues trying to cope with the consequences of the state crackdown.
"In some cases patients were removed from ventilators and other medical equipment. They said: 'Let them die. They have no rights. They are against the Islamic system, and they deserve to die.'"
Medical workers also told the doctor security officials targeted protesters with their weapons inside medical facilities.
"Some had been wounded by shotguns and (later) were killed in the hospital with live ammunition… (protesters) who had been shot with live bullets and were again killed inside the hospital with live ammunition."
As a result of the state crackdown, Dr Rahmani-Rad says the security forces are now effectively in control of the hospitals.
"If they realise that someone who was injured in the protests has gone to a hospital, or even if they had gone before and managed to escape them, they will arrest that person. By checking security cameras, they track them down, raid the locations, and detain them. This is the situation we're in right now."
Targeting doctors
Reports of doctors and medical professionals being targeted have circulated online.
So far, human rights organisations say they have verified six cases of medical professionals being arrested or detained for treating protesters.
Among these are Ameneh Soleimani, Babak Pouramin, and Farhad Nadali, colleagues whose arrests were confirmed by Dr Rahmani-Rad.
One of these doctors is Dr Alireza Golchini, who posted on Instagram earlier in January saying that he would provide treatment to protesters.
In recent days, human rights organisations say security forces raided Dr Golchini's home and beat him before detaining him.
Now, Dr Golchini is reportedly facing the risk of execution, according to human rights organisation Hengaw, for charges of Moharrebeh - known as waging war against god.
How many people have been killed?
Iranian authorities violently shut down protests and enforced an internet blackout that was largely in place from eight to 27 January.
This has obscured the true impact of the brutal crackdown and made it difficult to collect verified data on the numbers of people killed and injured during the uprising.
Iran's Islamic Republic has said 3,117 people have been killed - claiming the majority of these deaths were security forces and civilians, not protesters.
Human rights agencies warn numbers are much higher.
The Human Rights Activists News Agency (HRANA) has independently verified 6,301 deaths, with a further 17,091 cases under review, bringing the possible total up to over 23,000.
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Medical professionals also claim the authorities' figure is too low.
Dr Rahmani-Rad and his network of doctors previously estimated around 20,000 to 30,000 people have been killed, and now believe it could be higher.
This number is echoed by Dr Amir-Mobarez Parasta, an eye surgeon based in Germany and a supporter of Reza Pahlavi, the son of the former Shah of Iran.
He claims at least 25,654 deaths have been recorded in hospitals and clinics across Iran since the protests began up to 23 January. Nearly a third of these (8,354) were in Tehran alone.
Sky News has approached the Iranian embassy for confirmation of these figures, but received no response.
Dr Parasta says he has collected figures on clinically reported deaths which have been linked to the protests, by speaking to medical professionals in hospitals and clinics across Iran. He says figures were verified by at least two individuals in each medical organisation.
Sky News has not seen these clinical reports and is unable to independently verify the figure.
Seeking care from overseas doctors
Injured protesters who require medical care are faced with a terrible dilemma. By seeking treatment at a clinic or hospital in Iran, they risk arrest and detention by the authorities.
Instead, some are turning to doctors who work overseas.
Dr Panteha Rezaeian is a cardio-vascular expert in California who has received numerous calls from protest participants or members of their families.
"They already had been shot. They couldn't go to any hospital because they are afraid of getting killed or arrested. So what's happened? They are inside the house. They have infections, some of them are still bleeding. Some of (them) have been shot inside the belly."
Dr Rezaeian told us about her most recent call.
"I have one very young boy that has been shot. From just a two-metre distance into both knees. And you can imagine he cannot ever walk again."
It is an extreme form of remote health care and the specialist says she does what she can, but these are people who need urgent care.
"Many of the injured people are not going (to hospital) and then what does mean? So it means they are at the risk of potential death in the next few days or a week."
Sky News approached Iranian officials with our findings and received no response.
(c) Sky News 2026: Doctors share disturbing accounts of Iran crackdown
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