Updated 1:10 a.m. ET Thursday
It had been just about 24 hours since a magnitude 6.4 earthquake rattled Taiwan's east coast, crumbling walls and knocking tall buildings askew, when rescue workers felt another big rumble late Wednesday. A quake — this time magnitude 5.7 — had just struck again near the city of Hualien.
Still, even amid dust and heavy rain and shattered glass, the scale of the devastation was becoming clear as night settled in: At least 10 people have died, more than 260 are injured and nearly 60 remain missing, according to Taiwan's state-run Central News Agency and figures from the National Fire Agency.
"This is the worst earthquake in the history of Hualien, or at least over the past 40 years that I've been alive," volunteer rescue worker Yang Hsi Hua told Reuters outside the Marshal Hotel, one of the buildings worst hit by the quake.
"We've never had anything like this; we've never had a building topple over. Also, it was constantly shaking, so everyone was really scared. We ran to empty open spaces to avoid it."
Another center of rescuers' focus Wednesday was a residential building where certain parts of the lower floors collapsed, causing the 12-story structure to lean at an unsettling 40-degree angle.
The Associated Press reports scores of rescue workers had gathered around the building, using cranes, excavators, ladders and their bare hands to scrape away the concrete for presumed trapped survivors.
"I saw the first floor sink into the ground. Then it sunk and tilted further and the fourth floor became the first floor," one local resident, who was nearby when the main earthquake struck overnight Tuesday, told Agence France-Presse.
"My family were unhurt, but a neighbour was injured in their head and is bleeding. We dare not go back home now. There are many aftershocks and we are worried the home is damaged."
An octogenarian resident was inside his apartment at the time of the quake.
"Everything fell down," he told AFP. "My bed was completely vertical, I was sleeping and suddenly I was standing."
He was rescued from the building, as were many others. At the start of the day, Taiwanese President Tsai Ing-wen tweeted that 145 people were unaccounted for; by nightfall, CNA reported that number had fallen to 66.
Taiwan is "grateful to the many offers of assistance & support coming from around the world," Tsai, who was in the city Wednesday to view the damage, said toward the end of the day on Twitter. "Although relief efforts in #Hualien are sufficient, your warmth & kindness have been felt by people of Taiwan."
At the same time, concern remains that further danger awaits the city of 100,000 in the days to come. In fact, a 6.1 magnitude quake hit roughly the same region just northeast of the island on Sunday, and more than a dozen tremors magnitude 4.5 or higher have shaken the city since Tuesday's earthquake.
The government is expecting more aftershocks in the next two weeks.
"Since the aftershocks are frequent, we urge all our compatriots ... to remain vigilant and always pay attention to the correct message from the government," Tsai said in a Facebook post. "This is when the Taiwanese people show their calmness, resilience and love. The government will work with everyone to guard their homeland."
"Keep hope," she added in another post, "never give up, cheer for Hualien."
NPR's Wanyu Zhang contributed to this report.