Taipei: At least 41 people were killed in a deadly train derailment in Taiwan's in Hualien county on Friday, officials said, adding 72 passengers were still trapped.

At 9.28 a.m. (local time), the Taiwan Railways Administration (TRA) No. 408 Taroko train en route from Shulin, New Taipei, to Taitung, suddenly derailed as it entered the Daqingshui tunnel, reports Taiwan News.

The train comprised eight carriages and had more than 350 passengers on board.

The accident took place on the first day of a four-day break for Taiwan's annual tomb-sweeping tradition.

According to the National Fire Agency, 41 people were killed and at least 66 were injured and are being treated in hospital.

According to a preliminary investigation, workers at a nearby tunnel project parked the vehicle at the top of a slope without fastening the handbrake.

As the train passed, the vehicle rolled down the slope and hit the eighth and last carriage, Taiwan News reported.

Prosecutors have reportedly questioned the person in charge of the tunnel project to find out why the vehicle had not been parked properly.

Premier Su Tseng-chang expressed his apologies to the passengers and sent his condolences to the victims' families, dpa news agency reported.

"I want to express my deep sympathies to the victims' families and to the passengers who were injured," Su told a news conference in Taipei, adding that he regretted the incident.

He said he would immediately leave Taipei for Hualien.

President Tsai Ing-wen has instructed the authorities to continue their rescue activities and to comprehensively investigate the cause of the accident.

The last major train crash in Taiwan was in October 2018, when 18 people died.