Some 400 people including medical staff, patients and the displaced have been released after being detained by the Israeli military during the storming of Kamal Adwan Hospital in northern Gaza, Al Jazeera correspondents report.

Some arrived in the Jabalia an-Nazla area of northern Gaza on foot. They said they were beaten with rifle butts and left out in the cold for long hours, including those who were injured and the elderly.

Medical staff said direct bombing hit the archive, sterilisation and maintenance departments, igniting a fire that quickly spread to the patients’ wards, operating rooms and laboratory.

Some attempted to extinguish the flames using water from the dialysis machine, which was mixed with chlorine, and suffered burns to their hands and faces.

The fate of the director of Kamal Adwan Hospital, Dr Hussam Abu Safia, is still unknown.