The strain of coronavirus found in the recent outbreak of COVID-19 in Jilin, Jilin province, were all the Omicron variant, an official said on Wednesday.

"The number of confirmed cases is increasing rapidly," said Sun Dianwei, director of the city's center for disease control and prevention, at a news conference on Wednesday afternoon. "The epidemic is on the rise and there has been community transmission."

As of Tuesday, the city had reported 161 locally transmitted COVID-19 cases and 142 asymptomatic carriers since the first four positive cases were found on March 2. All 303 patients have been sent to designated hospitals for quarantine and treatment.

The city started its fourth round of mass testing at noon on Wednesday and is expected to be finished by 6 pm.

On Monday, all residential communities in the downtown area of the city were placed under lockdown management, and residents were asked not to leave home unless necessary, according to Luo Bing, Party secretary of the city's health commission.

"Two designated hospitals, including Jilin Hospital for Infectious Diseases and Affiliated Hospital of Jilin Medical University can provide 552 beds for infected patients," Luo said. "Another three makeshift hospitals with around 1,200 beds are being prepared."

Positive cases related to Jilin city were also reported in the provincial capital of Changchun.

As of Tuesday, the city has reported 48 local cases and 21 asymptomatic carriers since the first positive case was found on March 3.

"The first case traveled to Jilin city several times before being diagnosed as COVID-19," Jiang Hongbo, deputy director of the Changchun health commission said at a Wednesday news conference.

"The epidemic in Changchun is on the rise, and the number of cases may increase," said Zhang Xingguo, director of the city's center for disease control and prevention. "There are also some infected students in the schools."

Jilin province reported 94 new local confirmed cases on Tuesday, including 73 in Jilin city, 12 in Changchun and nine in Yanbian Korean autonomous prefecture.

Another 80 asymptomatic carriers were detected, including 65 in Jilin city, 10 in Changchun, two in Yanbian, two in Meihekou and one in Songyuan.

Contact the writer at zhouhuiying@chinadaily.com.cn