Yangzhou, Jiangsu province, has seen a dramatic drop in coronavirus cases after the city, which has a population of 4.5 million, introduced stringent public health measures to combat COVID-19.

While the total number of locally transmitted cases has reached 555 since July 20, Yangzhou only reported three cases on Monday, according to the Jiangsu Health Commission. Now, Jiangsu has 725 patients receiving treatment in the hospital.

Nanjing, the provincial capital, has reported no new cases for four consecutive days. Nanjing police on Monday reported 94 cases of locals refusing to follow the virus containment protocol to play mahjong and poker and visit karaoke clubs.

They also asked local people to avoid gatherings and keep a social distance, as cluster infections of COVID-19 in Yangzhou originated at mahjong parlors.