Chinese President Xi Jinping has ordered all-out rescue efforts to minimize casualties as a 6.8-magnitude earthquake killed at least 21 and injured dozens of others in southwest China’s Sichuan Province on Monday afternoon.

Chinese state media quoting local authorities reported the earthquake jolted a mountainous area of Luding County in Sichuan at around 1 pm. Nearly 350,000 residents have been affected, according to reports. Monday’s earthquake added to the difficulties of the people as Sichuan is already battling a prolonged drought, power shortages and a Covid-19 outbreak that has put the capital Chengdu under lockdown.

Authorities in Chengdu imposed a lockdown from Thursday evening amid a growing Covid-19 outbreak. Residents were told to stay home, with one person per household allowed out each day to buy necessities. Social media users criticised the strict Covid-19 restrictions in place, saying their fire escapes were blocked, or that community staff would not let those under quarantine run outside to safety.

According to local media reports at least 31 people were injured, with rescue efforts continuing into the night. Severe tremors were reported by residents of Chengdu, and the nearby cities of Mianyang and Meishan, where cracks appeared in buildings. Neighbouring Chongqing municipality and three other provinces – Yunnan, Shaanxi and Guizhou – were also heavily jolted by the quake.

The state news agency also reported rubble piled up on a highway leading to a major bridge towards Luding. The local government said that a number of main roads, telecoms lines and houses had been damaged and officials were still trying to determine the extent of impact. At least six moderate aftershocks were recorded until 4pm, with more expected, the authorities said.

Sichuan is among China’s most quake-prone provinces as it straddles a major fault line. According to reports, in 2008, a magnitude 8.2 quake about 80km from Chengdu left more than 69,000 people dead. Another in 2013, hitting at magnitude 7.0 near Yaan, claimed nearly 200 lives.

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