A photo posted to social media of a building in Hualien, Taiwan.
Rescuers are working to reach five people trapped and more than 140 people unaccounted for in several buildings damaged by a strong earthquake near Taiwan's eastern coast.
The shallow, magnitude 6.4 quake today caused at least four buildings in worst-hit Hualien county to cave in and tilt dangerously, killing four people.
Video footage and photos showed several midsized buildings leaning at sharp angles, their lowest floors crushed into mangled heaps of concrete, shattered glass, bent iron beams and other debris.
Firefighters could be seen climbing ladders hoisted against windows as they sought to reach residents inside apartments.
The quake injured 225 people, two dozen of them critically, in Hualien county, Taiwan's Central News Agency reported. The force of the tremor buckled roads and disrupted electricity and water supplies to thousands of households, the National Fire Agency said.
Taiwanese President Tsai Ing-wen moved to reassure the Taiwanese public that every effort would be made to look for survivors. In a post on her official Facebook page, Tsai said she arrived in Hualien today to review rescue efforts.
Tsai said she "ordered search and rescue workers not to give up on any opportunity to save people, while keeping their own safety in mind.""This is when the Taiwanese people show their calm, resilience and love," she wrote.
"The government will work with everyone to guard their homeland."
The official news agency said all but two of the 145 people who could not be reached might be in the Yunmen Cuiti building, a 12-story apartment building, though it said it did not immediately have an estimate of how many were trapped.
Chen Tzai-Tung, a worker with the government disaster center, said it was not safe for rescuers to enter the Yunmen building because it was still leaning farther bit by bit.
The headcount of missing people is based on registered occupants, Chen said by phone, adding that firefighters were evaluating whether to prop up the building with steel.
"It's still in the process of tilting, so it would be dangerous to go in there," Chen said.
"They're scrambling for time."
A hotel employee died when the ground floor caved in at the Marshal Hotel, and another person died in a residential building, the agency reported.
A maintenance worker who was rescued after being trapped in the hotel's basement said the force of the earthquake was unusual.
"At first it wasn't that big ... we get this sort of thing all the time and it's really nothing. But then it got really terrifying," Chen Ming-hui said after he was reunited with his son and grandson.
"It was really scary."
Other buildings shifted on their foundations and rescuers used ladders, ropes and cranes to get residents to safety.
Taiwanese media reported that a separate hotel known as the Beautiful Life Hotel also was tilting.
Taiwan's Central News Agency posted photos showing a road fractured in several parts.
Bridges and some highways were closed pending inspections.
With aftershocks continuing through the night, residents were being directed to shelters, including a newly built baseball stadium, where beds and hot food were provided.
Speaking from a crisis center in Taipei, Cabinet spokesman Hsu Kuo-yung said rail links appeared to be unaffected and the runway of Hualien airport was intact.
"We're putting a priority on Hualien people being able to return home to check on their loved ones," Hsu said.
Schools and offices in Hualien County were to be closed Wednesday.
The US Geological Survey said the quake struck just before midnight Tuesday about 21 kilometers northeast of Hualien at a relatively shallow depth of about 10.6 kilometers.
Taiwan has frequent earthquakes due to its position along the "Ring of Fire," the seismic faults encircling the Pacific Ocean where most of the world's earthquakes occur.
Exactly two years earlier, a magnitude 6.4 quake collapsed an apartment complex in southern Taiwan, killing 115 people.
Five people involved in the construction of the complex were later found guilty of negligence and given prison sentences.
A magnitude 7.6 quake in central Taiwan killed more than 2,300 people in 1999.