Police in Yangzhou, Jiangsu province are investigating a 64-year-old woman, who is the city's first locally transmitted confirmed case of COVID-19 in the new outbreak, for impeding the prevention of infectious diseases.

The woman, surnamed Mao, arrived in Yangzhou from Nanjing on July 21, when Nanjing had already banned people in risky areas from leaving the city.

Without reporting to her local community, she visited Yangzhou's restaurants, stores, walk-in clinics, farm product markets and mahjong lounges frequently in the subsequent six days.

Mao was discovered when she went to a hospital for cough and fever on July 27 and was found to be infected with COVID-19 the next day. She still refused to share how many places she had visited when police launched an investigation.

Mao has been transferred to Nanjing's designated hospital for treatment.

Mao's neglect of regulations resulted in the wide spread of COVID-19 in downtown areas of Yangzhou and had severe ramifications, police said.

The case is still under investigation.