Amnesty International reported the misuse of hospitals by Hamas in 2015?
"In a 2015 report, Amnesty said Hamas had commandeered a disused outpatient clinic at al-Shifa to interrogate, torture and kill opponents, in what Hamas enforcers dubbed “Operation Strangling Necks”.
The victims were people accused of collaborating with Israel, or of working with the rival Palestinian Fatah movement.
Abandoned areas of Shifa hospital “including the outpatients’ clinic area”, were used “to detain, interrogate, torture and otherwise ill-treat suspects, even as other parts of the hospital continued to function as a medical centre”, the Amnesty report noted.
One Fatah activist told Amnesty he suffered two hours’ torture at the outpatients’ clinic, being beaten with a hammer while blindfolded and trussed.
The report, which investigated dozens of extrajudicial executions by Hamas’s “internal security” agents, also said victims’ bodies would be dumped at Shifa’s morgue so that families could collect them. Many bore signs of torture and multiple gunshot wounds.
Philip Luther, Amnesty International’s Middle East and North Africa director, said at the time that Hamas’s actions were “spine-chilling” and “in some cases amount to war crimes”."
https://www.telegraph.co.uk/world-news/2023/11/12/hamas-keeping-civilians-in-hospitals-gaza-netanyahu/ (paywalled so I've copied the relevant bit)