Inside her tent in the displaced persons camp in the Al-Mawasi area south of Khan Younis, Nadia and her three children count the days with great patience since her husband, Dr. Hassan al-Khalil, was detained in Israeli prisons as part of a wave of arrests following the devastating bombardment of hospitals in the Gaza Strip.

The last time Nadia saw her detained husband was in October 2024 at Kamal Adwan Hospital, where he worked as a vascular surgeon and remained until the last moment despite the Israeli siege.

Hassan al-Khalil is one of at least 15 Palestinian doctors from Gaza currently held in Israeli prisons, most notably Hussam Abu Safiya, director of Kamal Adwan Hospital.

Hussam Abu Safiya was among the Palestinian doctors who refused to abandon dozens of newborn infants they were treating after the Israeli army ordered the forced evacuation of the hospital.

When Israeli soldiers stormed the hospital with tanks, they ordered families to leave. Nadia said they pledged not to harm the doctors but did not keep their word. That night was her last meeting with her husband.

Naji Abbas, of the Israeli organization Physicians for Human Rights, which deals with the cases of abducted doctors, dates the arrest of Hassan al-Khalil to October 25, 2024, two months before Israeli forces arrested Abu Safiya.

An Israeli law authorizes the indefinite detention of those classified as unlawful combatants, a classification that Abbas says does not exist in international law.

Nevertheless, Abu Safiya has now spent over 18 months in Israeli prisons. His lawyers and human rights organizations say credible reports indicate he has suffered violations including severe torture and that his life is in danger.

In contrast, Hassan al-Khalil has spent nearly 21 months in Israeli detention without any charge being filed against him. He was initially transferred to the notorious Sde Teiman detention facility, where he was held for seven months. According to his wife, he still does not know that he lost his father.

Abbas, a member of Physicians for Human Rights Israel, believes that what happened at Kamal Adwan Hospital is part of systematic efforts by Israel to target Gaza hospitals and displace Palestinians from them.

He added: Every time the Israeli army raided a health facility, it arrested dozens of its workers, noting that more than 350 healthcare workers have been arrested during the genocidal war, leading to a complete collapse of health services in the northern Strip.

According to the Gaza Ministry of Health, 94% of health facilities that were operational before October 2023 are now out of service due to destruction.

This severe shortage in health services puts the lives of more than 42,000 people with serious injuries at risk. In total, there are over 173,000 wounded suffering from injuries caused by Israeli bombardment.

Physicians for Human Rights Israel reports that about 55 healthcare workers are still detained by Israel, including 15 doctors. Meanwhile, Nasser Odeh, Abu Safiya's lawyer, earlier told Al Jazeera that more than 100 medical staff remain detained in occupation prisons without any charges.

The organization filed a petition with the Israeli Supreme Court to release the captive doctors. In the absence of a response to the request, the suffering of these detainees continues like other prisoners amid ongoing violations inside prisons, including starvation, physical abuse, and sleep deprivation during daytime hours, as documented by human rights reports.

Lawyers quoted testimony from Hassan al-Khalil that lights in the cells are never turned off at night and detainees are not allowed to sleep during the day; if they doze off, soldiers shout through loudspeakers.

But al-Khalil's suffering, as reported by Physicians for Human Rights, does not end there. He suffers from diabetes and high blood pressure. Abbas said he is periodically deprived of his medication, and he was left with scabies without treatment for weeks.

His wife said that other Palestinian prisoners released by Israel told her that her husband has lost 40 kilograms.

Al Jazeera contacted the Israel Prison Service and the Israeli army for comment on the various allegations raised by families of detainees and their lawyers, but received no response from either.

When asked why the doctors continue to be imprisoned without charges months after the ceasefire between Israel and Hamas, Abbas said: We believe that the State of Israel fears the voices of Dr. Abu Safiya, Dr. Hassan al-Khalil, and other doctors.

Abbas added that during a court hearing in June, an image of Abu Safiya also circulated online showed Israeli guards beating him brutally with hammers and clubs.

Lawyers for Hassan al-Khalil said they have seen him only four times since his arrest. The last time was in January, then visits stopped after the United States and Israel launched a war on Iran in late February.