Authorities in the north central Thanh Hoa Province penalized Kim Xuan Do, 38, a primary school teacher, on Sunday.

On July 23, Do who lives and works in Da Nang, returned to his hometown in Thanh Hoa’s Nong Cong District to visit relatives. Four days later he went to a local medical center to make mandatory health declarations and was instructed to quarantine himself at home for 14 days.

But on August 5, when local authorities went to check on him, he was not at home and had instead gone out to play sports.

Thanh Hoa has so far reported one infection related to the Da Nang outbreak.

Duong Ngoc Khanh, 19, was fined in nearby Ha Tinh Province. The student of the Da Nang University of Architecture took a bus home -- in Thach Ha District -- two weeks ago.

He too was quarantined at home for 14 days, and he was not at home when local authorities came to check on August 6.

He said he had gone to a bank, where three employees were then told to quarantine themselves.

Da Nang recorded the first local case of infection on July 25 to end the country’s 99 days without community transmission, and all localities are screening people returning from that city since July 1.

Since the fresh outbreak began, 355 people have tested positive for Covid-19 in 15 provinces and cities, including Hanoi and Ho Chi Minh City. So far 13 people have died.

Health authorities have repeatedly called on those who have visited stricken areas to file health declarations for testing and quarantining.