China has reported its highest daily number of local coronavirus cases in months as mass testing and contact tracing campaigns uncover a trail of Delta variant infections, reports AFP.

Health authorities have reported 71 new domestic cases, the highest since January, as China battles its largest outbreak in months by testing entire cities and locking down millions.

Beijing had previously boasted of its success in crushing Covid-19, allowing the economy to rebound and normal life to return while swathes of the globe struggled to douse a pandemic that has killed more than four million people worldwide. But the latest outbreak is threatening that record with nearly 500 domestic cases reported since mid-July, when a cluster among airport cleaners in Nanjing, Jiangsu province, was found.