Yangzhou, Jiangsu province, reported 37 new locally transmitted cases of COVID-19 on Wednesday, the provincial Health Commission said on Thursday.

It has registered 485 locally transmitted cases since July 20, while Nanjing, the provincial capital, has seen 234. Of the 702 cases being treated in Jiangsu's designated hospitals, 24 are in serious condition and 13 are critical.

Chinese Vice-Premier Sun Chunlan stressed stricter efforts in quarantine, contact tracing and organization of nucleic acid sample collection to contain the virus in Yangzhou.

Sun, also a member of the Political Bureau of the Communist Party of China Central Committee, made the remarks when she inspected Yangzhou on Wednesday.

Sun met with Jiangsu's Party Secretary Lou Qinjian, Governor Wu Zhenglong and relevant departments to analyze the current pandemic situation to improve the virus control work.

On Wednesday night, Nanjing's anti-graft body announced that three officials working at the city's Lukou subdistrict had been detained by discipline inspection authorities on suspicion of serious violations of Party discipline and laws for allegedly failing to properly perform duties to contain the virus.

The Nanjing Lukou International Airport, located at the subdistrict, was found to be neglecting sanitation and change-of-clothing protocols when monitoring its cabin cleaners, which resulted in the virus being transmitted to many cities across the country.