With much of the train still trapped in the tunnel, escaping passengers were forced to scale doors, windows and roofs to reach safety.
A passenger train smashed into a vehicle on its tracks and partially derailed outside a rail tunnel in Taiwan on Friday, and police said at least 34 people were killed and dozens injured.
"In response to a train derailment in Hualien, Taiwan, our emergency services have been fully mobilised to rescue and assist the passengers and railway staff affected", she said in a Twitter post on Friday.
Between 80 to 100 people have been evacuated from the first four carriages of the train, while carriages five to eight have "deformed" and are hard to gain access to, it added.
Officials said the accident could have been caused by a maintenance vehicle sliding down an embankment and striking the train before it entered the tunnel near the coastal city of Hualien.
Local media pictures from the scene showed the back of a yellow flatbed truck on its side next to the train.
Tsai Ing-wen, the President of Taiwan, called it a "heartbreaking incident" in a tweet this morning.
"We broke the window to climb to the roof of the train to get out", she added.
The train was carrying around 350 people, the fire department said.
"It felt like there was a sudden violent jolt and I found myself falling to the floor", an unidentified female survivor told the network.
Today was the start of the annual "Tomb Sweeping" holiday, a time when Taiwan sees a surge in travel.
Taiwan's mountainous east coast is a popular tourist destination, and the railway line from Taipei down the east coast is renowned for its tunnels and route that hugs the coastline. More than 72 people were injured, with around 60 already sent to a hospital.
In 1991, a collision in western Taiwan killed 30 people and injured 112 in the country's deadliest train accident.