The crash on Friday was Taiwan's worst rail accident in seven decades, when an express train hit the truck that had slid down a bank beside the track from the building site. Officials are investigating the manager of the construction site, Lee Yi-hsiang, whose truck is suspected of not having its brakes properly applied.
Taiwan's transportation ministry said 51 people died and many others were injured when a train carrying 490 people derailed in a tunnel north of Hualien.
As it approached a narrow tunnel, the train hit the errant truck that lay in its path, derailing numerous carriages as the devastation unfolded.
Surviving passengers had to escape the wreck by climbing out of the train's doors and windows, before walking along the transport vehicle's roof to get to safety, the Associated Press reported. She didn't offer details citing an ongoing investigation.
The Hualien district court allowed the truck owner to post bail of 500,000 new Taiwan dollars but he must stay in the county and avoid contact with any witnesses, Taiwan's Central News Agency reported. "After the whole rescue work is completed, I believe I will take the responsibility", he said.
The president's office said in a statement that she had ordered hospitals to prepare for the arrival of large numbers of injuries, stressing that "the priority is to rescue the stranded people". "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.The accident terrified passengers onboard. "At the beginning, they still responded when we called them".
Taiwan's transport ministry said two USA citizens were among the dead, while two Japanese, an Australian and a Chinese citizen were among the injured.
Workers removed the two rearmost cars from the tracks Saturday morning.
A rescue worker guides others as they remove a part of the derailed train.
As fix work takes place on the track from where the train derailed, trains will run on a parallel track, with a delay of 15-20 minutes.
Deputy Transport Minister Wang Kwo-tsai said late Saturday the railway administration needed to take hard look at all these issues.
The National Fire Service said the dead included the train's young, newly married driver and the assistant driver. The government's disaster response centre said it was the worst rail disaster in 73 years.
Friday's crash took place at the start of the Tomb Sweeping Festival, a four-day public holiday when many Taiwanese return to villages to tidy the graves of their ancestors.
In this photo released by the Taiwan Presidential Office, Taiwan President Tsai Ing-wen offers joss sticks at a memorial for victims of Friday's train derailment in Hualien, eastern Taiwan.
Taiwan is a mountainous island, and most of its 24 million people live in the flatlands along the northern and western coasts that are home to most of the island's farmland, biggest cities and high-tech industries.
Taiwan's eastern railway line, a popular tourist draw, winds its way through towering mountains and dramatic gorges before entering the picturesque Huadong Valley.