The fire department said in a statement that the train bound for Taitung derailed in a tunnel just north of Hualien City, causing some vehicles to collide with the tunnel wall.
She added that at least four people are believed to have died, three seriously injured people have been taken to hospital, and about 20 with minor injuries are waiting to go to the hospital.
The department said the train was carrying about 350 passengers and that rescue efforts were continuing.
She added that between 80 and 100 people had been evacuated from the train’s first four cars, while the five to eight wagons were “deformed” and inaccessible.
“Is everyone in the fourth cart?” A woman’s voice was heard screaming from inside the tunnel, in the photos provided by the fire department.
The official Central News Agency said the truck, which “was not parked properly,” was suspected of slipping on the track of the train. The fire department showed a photo of what appeared to be the wreck of a truck lying next to a derailment of the train.
Pictures of the crash scene show vehicles inside the tunnel that collapsed and torn apart from collision, passengers collect bags and suitcases in a tilted and derailed carriage, and others walking along debris-laden tracks.
The accident occurred at the start of the long weekend of the traditional Tomb-Sweeping Day Hospital.
Taiwan’s mountainous east coast is a popular tourist destination.
In 2018, 18 people were killed and 175 injured when a train derailed in northeastern Taiwan, in the island’s worst rail disaster in more than three decades.
This is an urgent story. Follow-up updates.