NANJING -- East China's Nanjing cty, which witnessed the country's latest resurgence of cluster infections of coronavirus attributable to the Delta variant, cleared all medium and high-risk areas for COVID-19 on Thursday.

The city logged no new locally transmitted cases on Wednesday. A total of 235 locally transmitted confirmed cases had been reported in the city as of Wednesday since cluster infections began to emerge on July 20, when a number of airport cleaners were found to be infected during a routine testing, said Ding Xiaoping, deputy director of the Nanjing Health Commission.

Among all the confirmed cases, 75 had been discharged from hospital by the end of Wednesday, according to Ding.

Public transportation in Nanjing including metro lines will gradually resume normal operation. The city once had 32 medium and high-risk areas for COVID-19.

Infections caused by the highly contagious Delta variant have spread from Nanjing to over a dozen of Chinese provincial-level regions.

With strict prevention and control measures such as strict travel restrictions, China has seen a distinct downward trend in new locally transmitted COVID-19 cases, with only five new locally transmitted cases reported in the Chinese mainland on Wednesday.