An electrical fault has been blamed for a fire that killed six patients in the intensive care unit (ICU) of Johor Baru's Sultanah Aminah Hospital.
Police said early investigations showed faulty wiring caused a short circuit on the third floor of the hospital - one of Malaysia's busiest with 294 patients and 193 employees.
Patients were evacuated to other wards after the blaze broke out at 9am yesterday. Firefighters took two hours to extinguish it.
Victims were limited to the ICU ward, according to Southern Johor Baru police.
"Out of the seven patients, four women and two men have died, while one patient was saved. The patient experienced 80 per cent burns... while three staff suffered from smoke inhalation but did not suffer burns," said district police chief Sulaiman Salleh.
He added: "We believe that all the victims died due to suffocation caused by the thick smoke in the ward."
Some patients were being transferred to nearby hospitals, although the Johor Sultan has ordered that the royal ward at Sultanah Aminah be converted into a temporary ICU for now, Menteri Besar Khaled Nordin was reported as saying.
In a condolence message on Twitter, Prime Minister Najib Razak said "the government will undertake a detailed investigation as soon as possible to identify the cause of the fire and improve safety levels".
According to the fire brigade, a distress call was received at 8.56am.
"We deployed 10 fire engines with 160 personnel from Johor Baru, Tebrau, Kulai and Johor Jaya fire stations to the scene," said Johor Fire and Rescue Department director Othman Abdullah.
"The fire affected two floors of the main... building but we managed to stop it from spreading to other floors," he said.
Health Minister Subramaniam Sathasivam said his ministry "has taken all necessary rescue actions and precautions to safeguard the rest of the patients and staff, including evacuating them to ensure their safety".
However, Johor Health and Environment executive councillor Ayub Rahmat said the authorities hoped private hospitals would offer to take in other evacuated patients as Hospital Sultan Ismail was packed.
"We are looking into ways to accommodate the evacuated victims, as even Hospital Sultan Ismail is crowded with patients," he was quoted by The Star as saying.
Datuk Seri Subramaniam said in a press statement that the burn patient had been transferred to the nearby Sultan Ismail Hospital while 10 staff members were injured, with two warded for treatment at other hospitals.
Menteri Besar Khaled also announced an allocation of RM100,000 (S$33,500) from the state religious council to aid those affected by the fire.
The bodies of the six deceased are being held at Sultanah Aminah for a post-mortem.