Rescuers search for survivors in a collapsed buiding in Tainan City, southeast China's Taiwan, Feb. 7, 2016. The death toll has risen to 23 in a 6.4-magnitude earthquake hitting an area near Tainan early Saturday. (Xinhua)

 
The death toll from a powerful earthquake that struck southern Taiwan reached 23 by Sunday noon, the Tainan fire agency said.

The collapse of the Wei Guan building, the most seriously damaged building in the quake, killed 21, including six children.

Rescuers are racing against time to save more than 120 people who are still trapped in the rubble of the building.

Some of the island's high-speed rail lines have suspended operations.

More than 600 rescuers, including fire fighters and volunteers, as well as 105 fire engines and 44 ambulances have been involved in the rescue, the fire agency said.

The 6.7-magnitude earthquake hit Kaohsiung at 3:57 a.m. Beijing Time on Saturday at a depth of 15 kilometers, the China Earthquake Networks Center said.

Local monitoring authorities put the scale of the quake at 6.4 magnitude.

Previous reports said more than 460 people were injured.

In the historic city of Tainan, eight buildings collapsed and another five were damaged.

The Chinese mainland has offered help. While addressing a lunar new year gathering on Saturday morning, Premier Li Keqiang sent condolences to the victims.

The quake occurred two days prior to Spring Festival, the lunar new year holiday.

Many mainland netizens posted messages expressing sympathies to the Taiwan compatriots who are affected by the quake.

Rescuers search for survivors in a collapsed buiding in Tainan City, southeast China's Taiwan, Feb. 7, 2016. The death toll has risen to 23 in a 6.4-magnitude earthquake hitting an area near Tainan early Saturday. (Xinhua)

 

Relatives of trapped persons wait for rescue updates next to a collapsed buiding in Tainan City, southeast China's Taiwan, Feb. 7, 2016. The death toll has risen to 23 in a 6.4-magnitude earthquake hitting an area near Tainan early Saturday. (Xinhua)

 

Rescuers search for survivors in a collapsed buiding in Tainan City, southeast China's Taiwan, Feb. 7, 2016. The death toll has risen to 23 in a 6.4-magnitude earthquake hitting an area near Tainan early Saturday. (Xinhua)

 

Rescuers search for survivors in a collapsed buiding in Tainan City, southeast China's Taiwan, Feb. 7, 2016. The death toll has risen to 23 in a 6.4-magnitude earthquake hitting an area near Tainan early Saturday. (Xinhua)

 

A rescuer escorts a survivor from a collapsed buiding in Tainan City, southeast China's Taiwan, Feb. 7, 2016. The death toll has risen to 23 in a 6.4-magnitude earthquake hitting an area near Tainan early Saturday. (Xinhua)

 

Rescuers search for survivors in a collapsed buiding in Tainan City, southeast China's Taiwan, Feb. 7, 2016. The death toll has risen to 23 in a 6.4-magnitude earthquake hitting an area near Tainan early Saturday. (Xinhua)

 

Rescuers search for survivors in a collapsed buiding in Tainan City, southeast China's Taiwan, Feb. 7, 2016. The death toll has risen to 23 in a 6.4-magnitude earthquake hitting an area near Tainan early Saturday. (Xinhua)

 

Rescuers save a survivor from a collapsed buiding in Tainan City, southeast China's Taiwan, Feb. 7, 2016. The death toll has risen to 23 in a 6.4-magnitude earthquake hitting an area near Tainan early Saturday. (Xinhua)

 

"Let's pray for the Taiwan compatriots," wrote netizen "Zuo'an Houniao."