Beijing reported zero new local COVID-19 cases for Monday, the first time since the city found the new cluster of novel coronavirus infections on June 11, a senior official said on Tuesday at a news conference. 

"Beijing had reported new local cases in the single digits for eight days in a row before it dropped down to zero on Monday, which has proved the effectiveness of the city's control and prevention measures," said Xu Hejian, spokesman for the municipal government.

"However, zero new cases doesn't mean no risks," he said. "We have to keep vigilant to contain the epidemic continuously."

Starting on Tuesday afternoon, the first group of 5,000 people who are on staff at the Xinfadi wholesale market, the place where all the cases were related for this round of cluster infections, completed their centralized quarantine with negative testing results. They will be relocated with follow-up health monitoring and psychological guidance. 

Meanwhile, the Xinfadi market has completed final disinfection work. 

By Monday, Beijing's total number of confirmed cases was 335 since the city reported the first case on June 11. Fifteen patients have been discharged from the hospital and 320 are being treated at a hospital.