Rescuers work in front of a collapsed building in quake-hit Hualien County, southeast China's Taiwan, Feb. 7, 2018. Four people were killed and 225 were injured as of 10:40 a.m. Wednesday after a 6.5-magnitude earthquake hit Taiwan. (Xinhua/Yue Yuewei)

HUALIEN, Feb. 7 (Xinhua) -- Four people were killed and 225 were injured as of 10:40 a.m. Wednesday after a magnitude 6.5 earthquake hit Taiwan.

A total of 236 people have been rescued, but there are still 145 people missing, with 143 trapped in the Yun Men Tusi Ti building, according to the local disaster relief administration.

Five tourists from the mainland were found in disaster areas and two were injured in the earthquake, the injured have been sent to hospital.

One of the injured, from east China's Fujian Province, was in unstable condition and the other tourist, from Beijing, was slightly injured.

Zhang Zhijun, head of the Taiwan Affairs Office of the State Council(TAOSC), received details about the casualties, property losses and rescue work through a phone call with Fu Kun-Chi, head of Hualien County.

Zhang expressed deep condolences to all the victims and sincere regards to Taiwan compatriots who suffered, saying that people from the mainland were deeply concerned about the earthquake and could feel what their Taiwan compatriots felt.

Knowing that quake-hit areas were in need of professional rescuers, Zhang said that the mainland was willing to send rescue teams to help.

"We hope local people will overcome the difficulty and rebuild their home at an early date," he said.

Chen Deming, president of mainland-based Association for Relations Across the Taiwan Strait, also said the mainland was willing to assist disaster relief, including sending rescue teams to the island.

"The mainland is learning of the conditions of mainland tourists, students and spouses living in disaster-hit areas," said An Fengshan, spokesperson for the TAOSC.

According to the China Earthquake Networks Center (CENC), the earthquake jolted waters near Hualien at 11:50 p.m. Tuesday.

The epicenter was monitored at 24.13 degrees north latitude and 121.71 degrees east longitude, with a depth of 11 kilometers, according to CENC.

The earthquake was followed by a series of aftershocks including several measuring over magnitude 5.

It is the most severe earthquake to hit Hualien in five decades, and 26 aftershocks hit the county as of 9 a.m. Wednesday, according to Fu.

The earthquake also caused 200 households to lose power, and 35,000 households to lose their water supply, the local fire agency said

Since Feb. 4, more than 100 earthquakes have jolted the area. Taiwan's earthquake experts said more quakes might arrive in the coming weeks.