A 6.4-magnitude earthquake struck southern Taiwan early Saturday, toppling at least one high-rise residential building and trapping people inside. Firefighters rushed to pull out survivors.

The death toll has climbed to 13, and more than 100 people are still missing.

Taiwan’s Emergency Management Information center says that nine of the victims were found at a residential high-rise building that collapsed in the quake Saturday, and that the two others were killed by falling objects elsewhere in the city of Tainan.

Authorities say 475 people were injured, but 368 of them were discharged from hospitals by late Saturday afternoon.

Firefighters scrambled to the site with ladders, cranes and other equipment and pulled survivors from the building in the southern city of Tainan, footage from local TV broadcasters showed. It was unclear how many people were trapped inside. Some reports said dozens or scores of people might have been in the building at the time of the collapse.

The Taiwanese news website ET Today reported that two buildings toppled in Tainan, and that some water and gas utility pipes had ruptured. Sirens were wailing as city authorities responded to the quake, the news website said.

The temblor struck about 4 a.m. local time (2000 GMT Friday). It was located some 22 miles (36 kilometers) southeast of Yujing, and struck about 6 miles (10 kilometers) underground, according to the U.S. Geological Survey.

It was felt as a lengthy, rolling shake in the capital, Taipei, on the other side of the island. But Taipei was quiet, with no sense of emergency or obvious damage just before dawn.

About two hours after the tremor, Taiwanese television EBC showed live images of a rescue at a partially collapsed building in Tainan. In it, rescue workers operating under the glare of floodlights combed through twisted concrete and metal and encountering people, apparently residents, who appeared dazed but uninjured.

Other footage showed people with their arms around firefighters being helped from the building, and cranes were being used to search darkened parts of the structure for survivors. Newscasters said other areas of the city were still being canvassed for possible damage.

(Copyright (c) 2016 Sunbeam Television. The Associated Press contributed to this report. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed.)

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