Beijing reported four new locally transmitted COVID-19 cases on Monday, including two confirmed with light symptoms and two asymptomatic carriers, according to the local health commission.

The cases were reported in the districts of Changping, Chaoyang and Fengtai, according to Liu Xiaofeng, deputy director of the Beijing Center for Disease Prevention and Control, at a news conference on Monday afternoon.

The infections were detected among people who had returned to Beijing and they had been sent to hospitals for treatment, according to Liu.

Residents who have been to risk areas including Hainan province, the Tibet autonomous region and the Xinjiang Uygur autonomous region should report to their residential communities, hotels or workplaces for epidemic prevention measures accordingly.

"Epidemic prevention and control measures must not be slackened as Beijing is facing a peak of returning passengers from outside the city," he said.

Of the new cases, an asymptomatic carrier, surnamed Liu, has been investigated by local police in the Fengtai district, due to allegedly concealing their travel history before returning to Beijing.

Liu was suspected of concealing having visited medium and high-risk areas, which has led to 260 people designated as at risk for the virus.