More than 11.16 million out of nearly 11.18 million residents in Dongguan, which borders Guangzhou, the provincial capital, have received negative results in a citywide campaign of nucleic acid tests as of early Tuesday morning, a senior health official from the city said.

The manufacturing hub is a third city in the province with a population over 10 million, besides Guangzhou and Shenzhen.

Zhang Yalin, a senior inspector with the Dongguan City Health Commission, said medical workers had worked around the clock to screen possible COVID-19 patients and asymptomatic carriers when a local resident was detected to be a confirmed case on Monday.

More than 20,000 medical workers had collected samples from nearly 11.18 million people in Dongguan for nucleic acid tests during the campaign that took place between 8 pm Monday and 1 pm Tuesday, Zhang said at a press conference on Tuesday afternoon.

The patient, surnamed Jing, who was detected on Monday, is a resident student at the Dongguan campus of Guangzhou Xinhua University in Dongguan's Machong township.

Jing, 20, whose nucleic acid test came out positive on Monday, was determined by local medical experts to be a confirmed case with mild symptoms. He has now been sent to a local designated hospital for isolated treatment, Zhang said.

"In addition to the mass nucleic acid tests, relevant departments have immediately launched further epidemiological investigation and disinfection at the public venues Jing once visited," he said.

And about 20,000 staff, teachers and students from Jing's university were required to stay on campus on Monday.

Meanwhile authorities have temporarily closed all cyber cafes, singing and dancing halls, libraries, cultural centers, museums, indoor gymnasiums and related entertainment venues in the city to prevent and control the further spread of the coronavirus, he added.

According to statistics revealed by the Guangdong Provincial Health Commission on Tuesday, Guangdong reported two new local transmitted COVID-19 cases on Monday, with the other confirmed case being reported in Shenzhen.

The province, which has a population of more than 125 million, reported another five imported confirmed cases on Monday.

As of late Monday, Guangdong had reported a total of 2,707 COVID-19 patients, including 1,140 imported ones. And a total of 221 patients are still hospitalized for treatment.