Pham Duy Tuyen, director of the Hai Duong Center for Disease Control (CDC), said Thursday the province is performing contact tracing related to two local coronavirus cases: a 34-year-old woman working for Vietnam Poyun Electronics and a 32-year-old woman who tested positive upon landing in Japan. The woman in Japan has been revealed to be infected with a coronavirus variant originated from the U.K., which is believed to be 70 percent more contagious than ordinary strains.

The Ministry of Health on Thursday morning identified 84 new local patients, with 72 linked to the woman working for Hai Duong’s Poyun firm and 10 to a 31-year-old man working at Van Don International Airport in Quang Ninh and living in Hong Ha Ward of Ha Long Town.

It is not known yet how the woman was infected, while the man may have come in contact with Covid-19 patients arriving from abroad on repatriation flights.

A total 3,000 people in Hai Duong, including those in Kim Dien Village of Hung Dao Commune and employees of Poyun, are being screened for the novel coronavirus, said Tuyen, adding the province could test 1,000 samples a day.

"Within today, the province would try to collect all samples of Poyun employees and residents of Kim Dien Village," he noted.

Hai Duong’s Chi Linh Town, where the Poyun firm is located, has been put under lockdown for 21 days starting Thursday noon, according to a directive issued by Prime Minister Nguyen Xuan Phuc. No public activity and no passenger transportation out of the city is allowed within the time period, unless in exceptional cases, the directive said. Personal vehicles are limited as much as possible. Transportation of materials and goods however are still allowed.

Besides Chi Linh, home to 220,000 people, other towns and localities in Hai Duong would undergo laxer social distancing measures, where activities involving large crowds are suspended. Factories in the province which don’t abide by Covid-19 prevention measures would have to stop operating.

The province government has also stopped allowing workers entering from outside of Vietnam to either enter the province or be quarantined there starting Thursday. The decision however doesn’t apply to foreign workers and experts approved by Hai Duong People's Committee to enter and be quarantined in the province before Thursday.

So far, 237 people, who worked at Poyun and had come in close contact with the infected 34-year-old woman, have been quarantined. The entire Kim Dien Village has been put under lockdown, while other villages in Hung Dao have implemented social distancing. Checkpoint stations have been erected to control traffic in and out of Hung Dao, and a section of Poyun closed down.

Vietnam has reported 1,635 Covid-19 cases so far, 167 of them active, and 35 deaths.