Quang Ninh Province has shut down all tourist attractions and historical sites, including the UNESCO-recognised heritage site of Ha Long Bay, Bai Tu Long Bay and religious sites.
Local authorities have also required people to strictly conform to social distancing measures and hygiene.
Meanwhile, Haiphong City will close tourist, historical and religious sites as well as amusement centres and street food stalls from Thursday midnight, including tourism services in Cat Ba Town in Cat Hai District.
People in Cat Hai District are asked to suspend wedding parties or simplify them.
Funerals also need to reduce the number of participants.
Local restaurants are requested to ensure safety distancing between people.