SEOUL, Jan. 26 (Xinhua) -- South Korean Prime Minister Lee Nak-yon ordered a probe into the cause of a deadly hospital fire on Friday that has killed 37 and injured dozens in the southeastern city of Miryang, local media said.

"There can be questions about how this amount of damage occurred in such a short period of time," Yonhap News Agency quoted Lee as saying. "We have to offer convincing explanations to the people in a detailed and transparent manner and determine who is responsible."

In Miryang, Lee also offered an apology, saying the government previously vowed to prevent such a disaster from happening again after a fire claimed 29 lives in December.

Friday's blaze is the worst fire the country has witnessed in more than a decade.

The blaze happened at about 7:30 a.m. local time Friday (2230 GMT Thursday) at the Sejong Hospital in Miryang city, South Gyeongsang province. It started in an emergency room on the hospital's first floor.

At least 37 people were confirmed dead, and tens of others injured. The death toll could rise as many were suffering serious injuries.

About 100 patients were originally in the hospital, some 390 km southeast of the capital Seoul. All of the 93 patients at an adjacent nursing home were evacuated safely.

The hospital was reported to have treated patients suffering mainly from cerebrovascular disease and stroke.

South Korean President Moon Jae-in convened an emergency meeting with his senior secretaries, ordering a thorough response to the blaze. The presidential Blue House ordered the national crisis management center to deal with the disaster.

The fire came just about a month after a building fire accident which killed 29 people in Jecheon city, North Chungcheong province, roughly 170 km southeast of Seoul.