A 7.0-magnitude earthquake has killed at least 19 people and injured 247 in China's Sichuan province, authorities said on Wednesday.
The earthquake hit Jiuzhaigou county, a popular tourist destination, at 9.19 p.m. on Tuesday at a depth of 20 km, Xinhua news agency cited China Earthquake Networks Centre as saying.
A separate 6.6-magnitude tremor struck Xinjiang province on Wednesday, injuring 32 people.
Rescue workers were assisting stranded tourists at Jiuzhaigou and more than 45,000 tourists were evacuated. Over 800 workers were combing villages in search of anyone still trapped, authorities said.
China's Earthquake Administration (CEA) said more than 1,000 aftershocks had been detected, with the most powerful reaching 4.8 magnitude on Wednesday, BBC reported.
The National Disaster Reduction Centre of China estimated that at least 24,000 homes were destroyed or seriously damaged in the Tuesday quake.
Chinese President Xi Jinping called for all efforts in the rescue operations while Prime Minister Li Keqiang urged the local government to assist the injured.
The Red Cross Society of China's statement said it had deployed emergency crews and volunteers to assist affected communities.
The second quake in Jinghe county in Bortala prefecture in Xinjiang province happened at 7.27 a.m. on Wednesday at a depth of 11 km. Of the 32 injured, two were in a serious condition.
About 600 houses and livestock sheds were damaged in neighbouring Ili Kazakh prefecture. Services of 40 passenger trains were stopped and 21 others suspended.
Earlier reports said residents in Jinghe county and the cities of Urumqi, Changji, Yining and Karamay felt strong tremors that lasted 10 to 20 seconds.
The epicentre was 37 km from Jinghe county seat, 93 km from Bole city, and 383 km from Urumqi.
Jinghe county has a population of about 150,000. A total of 65 quakes greater than magnitude 3 have been recorded within 200 km of the epicentre over the past five years, the current being the greatest.
Gwendolyn Pang of the Red Cross Society of China said it would take time to learn the extent of the damage and exact number of casualties.
"Communications lines and electricity are disrupted and people are no doubt shocked and scared," she said.