Millions of people in the Chinese megacity of Chengdu emerged Monday from a Covid-19 lockdown that had closed schools, disrupted businesses and forced residents to stay home for over two weeks.

With a population of 21 million, southwest China's Chengdu is the largest Chinese city to shut down since global finance hub Shanghai imposed a strict two-month lockdown in April, leaving many residents scrambling for food.

China is the last major economy welded to a zero-Covid strategy and officials are under pressure to curb virus flare-ups swiftly ahead of a key political meeting in mid-October.

"With the joint efforts of the whole city, the epidemic has been effectively controlled," the Chengdu government said in a statement Sunday.

Government departments, public transport services and companies were able to resume work on Monday, the statement said, after shutting down on September 1.

Chengdu will continue to conduct mass testing, and anyone who wants to enter a public area or take public transport will require a negative Covid test result within 72 hours -- similar to the rules in other large cities including Beijing and Shanghai.

Schools will re-open in an "orderly manner" and returning students will be strictly tested, the statement said.

Gyms, swimming pools, mahjong clubs and other indoor entertainment venues must all check whether patrons have a negative test result within 48 hours.

No new cases were reported in the city on Monday.

During the strict lockdown some residents confined to their homes could not even flee when a strong earthquake in a nearby part of Sichuan province reverberated through the city earlier this month, locals told AFP.

Chengdu will host the world team table tennis championships at the end of September in a "closed-loop" bubble that will be China's first international sports event since the Beijing Winter Olympics and Paralympics in February and March.

Quarantine bus crash

Several other cities including the southern tech hub of Shenzhen and Guiyang in south China, where Apple's China data centre is located, have all had targeted lockdowns and travel restrictions in recent weeks as officials rushed to curb mini outbreaks.

On Sunday, 27 people died en route to a quarantine facility when their bus crashed on a highway in rural Guizhou province in southwest China.

Authorities apologised and launched a probe into the accident, which sparked outrage online.

"What proof do you have that you won't be on that bus at night someday?" read one viral Weibo post with thousands of likes.

China reported 807 new domestic infections on Monday, the majority of which were asymptomatic, according to the National Health Commission.