China will lock down the southwestern city of Chengdu and order its 21 million people to stay home from 6pm on Thursday amid a growing Covid-19 outbreak . Chengdu , capital of Sichuan province, reported 106 new local symptomatic cases and 51 asymptomatic cases on Thursday. The city has recorded over 600 symptomatic cases since the outbreak erupted about a week ago. Citywide testing of residents will begin on Thursday and last until September 4, according to the Chengdu government. However, the city government is trying to avoid the chaos experienced during the Shanghai lockdown earlier this year by allowing one person in each household to leave to buy necessities once per day. The person must present a negative PCR test result when going out. Residents who require medical care or have special needs will be permitted to leave their homes with valid documents and negative PCR tests. Supermarkets, pharmacies, healthcare facilities, e -commerce operators and restaurants are allowed to remain open, although restaurants may only provide takeaway services. Other residents are required to work from home. The Chengdu government said on Tuesday that the rapid spread of cases was linked to two swimming pools. Sichuan province and nearby Chongqing municipality have been hit by a record-breaking heatwave in recent weeks. The government will allow limited public transport in the city, with subways and buses operating with lower frequency. Taxis and shared bikes will be allowed to continue to operate, but passengers must present negative PCR tests performed within 24 hours. Chengdu’s Shuangliu International Airport and Tianfu International Airport cancelled hundreds of flights on Thursday. The Chengdu lockdown came days after the southern tech hub of Shenzhen locked down large areas of the city. China tech hub Shenzhen on alert as new Omicron subvariant surfaces Shenzhen reported 62 new positive cases on Thursday, 27 of which were asymptomatic. The government said 26 of the new cases were linked to a dance studio, which has since been shut down. The government has launched an investigation into the case and the studio operator may be held responsible. Shenzhen scaled up the lockdown to cover its manufacturing centres on Tuesday. The city has shut down some subway stations and banned dining in restaurants in several districts this week. Meanwhile, the city of Dalian in the northeastern province of Liaoning is also battling a new wave of Covid-19 cases. The city reported four new local symptomatic cases and 101 asymptomatic cases on Thursday. Authorities said half of the cases could be traced to wet markets and 20 per cent of the cases might have been contracted on public transport. China has insisted on enforcing a zero-Covid policy as the country prepares for its most important political event of the year, the 20th Communist Party congress, to be held in mid-October. The country reported 307 new local symptomatic cases on Thursday, with 132 of them in Sichuan province. China has 1,596 new local asymptomatic cases, 621 of them reported in Tibet, which is reeling from a recent outbreak.