Jiangsu province identified 50 new locally transmitted cases of COVID-19 on Monday, the provincial Health Commission reported on Tuesday.

Of those infected, 48 were in Yangzhou and two in Nanjing. Yangzhou has registered 394 cases since July 20.

A total of 615 people with locally transmitted COVID-19 are receiving treatment in Jiangsu's designated hospitals. Twenty-six are in serious condition and six are critical.

More than half of the patients in Yangzhou are elderly — age 60 or older. Many were infected when gathering to play mahjong in dense crowds at lounges with poor ventilation.

Because improper procedures at a sample collection site, a man had infected at least 35 people as of Monday, including health workers and residents in Yangzhou.

The man, Wang Qiang, who worked for the government, ignored instructions to government employees not to visit gambling houses.

Now being treated in the hospital, he has been suspended and is under investigation.

Yangzhou started its fifth round of coronavirus testing in its downtown areas on Monday.

The provincial Health Commission had sent more than 4,000 medical workers to Yangzhou to help contain the virus and treat the patients.