Five fire trucks arrived at the scene after the fire started at the hospital’s Intensive Care Unit (ICU) at about 9am.

Hospital staff evacuated patients from the other wards to the main grounds outside the building, while tents were set up to provide shade for the patients.

Johor Baru (South) Police Chief ACP Sulaiman Salleh said those killed include four females, all of whom were believed to be patients.

He said authorities were still investigating the cause of the incident, adding that initial investigations showed it could have been due to a short circuit.

This is the second time a fire has broken out at a hospital.

Last July, 28 patients at KPJ Specialist Hospital in Damai, Sabah had to be evacuated when fire broke out at its main power control room, also believed to have been caused by a short-circuit.