Hainan will conduct nucleic acid tests for all people in the island province to curb the new COVID-19 outbreak, which has spilled over into 10 cities and counties across the island, according to a news conference held in Haikou on Saturday afternoon by the local authority.

Supporting teams with the State Council's joint prevention and control mechanism have arrived in Hainan to help cope with the fast changing situation, said Du Jianwei, an official with the Hainan Provincial Health Commission, at the meeting.

With the first confirmed case of COVID-19 detected on Monday in Sanya, the new outbreak has spilled over across Hainan island, with the total confirmed locally transmitted cases and asymptomatic carriers having reached 525 and 121, respectively, as of 12am on Saturday, said local officials.

Sanya, at the southern-tip of Hainan island, has reported 455 confirmed locally transmitted cases and 103 asymptomatic carriers from Monday to 12am on Saturday, according to the local COVID-19 epidemic prevention and control headquarters.

It said that Sanya has imposed a city-wide lockdown starting from 6am on Saturday. While services for basic social operations, epidemic prevention and control and emergencies are fully guaranteed, public movement is now under control and all public transportation services has been suspended.

The virus is the Omicron BA.5.1.3 variant. This is the first time it has been detected in China. Experts believe the origin of the virus was contaminated imported seafood at the Yazhou fishing port in Sanya or Hainan dealers who were most likely infected during transactions with overseas dealers, local officials said.

Travelers who are currently in Sanya, or have a travel history based in Sanya since July 23, will have to stay in Hainan temporarily. Nucleic acid tests will be conducted according to the requirements of local epidemic prevention and control authority. Future arrangements will be made according to the situation of epidemic prevention and control in Sanya, said officials at the news conference in Haikou.

The Sanya tourism authority said they have been doing their best to ensure good and comfortable services for tourists who are spending their summer holidays in the coastal city. The tourist destination attracted about 1.35 million visitors in July, according to figures from an airlines data provider.