CHONGQING, Dec. 1 (Xinhua) -- All of the nucleic acid test results were negative for contacts of the traveler from southwest China's Chongqing, who was initially diagnosed as an asymptomatic COVID-19 case upon arriving in the Republic of Korea (ROK), the health authorities of Chongqing said Monday.

The city has traced over 8,000 people who had contact with the traveler or with his close contacts, all of whom have tested negative in nucleic acid screenings, said the headquarters of COVID-19 prevention and control in Chongqing's high-tech industrial development zone.

The ROK national is an employee of a local company and had been in the municipality since Feb. 1. He traveled to the ROK Friday and was later diagnosed as an asymptomatic coronavirus case, according to earlier official announcements.

The company said the second nucleic acid test of the traveler in the ROK turned out to be negative.

Environmental samples from the company and the hotel, which had accommodated the ROK national, also tested negative for the virus.

The municipality has allowed the company and the hotels, which had been temporarily shut down due to the incident, to resume operation.