The tourists, mainly from Hanoi and HCMC, remain stuck in the central coast city of Da Nang due to imposed travel restrictions.

The city, a tourism hotspot, reintroduced social distancing measures for 15 days staring July 28 after confirmation of a resurgence of domestically-transmitted cases. Public transport services, including flights to and from the city with a population of 1.1 million people were suspended to contain a fresh Covid-19 outbreak.

Da Nang Chairman Huynh Duc Tho said: "It remains unknown when the Covid-19 outbreak would end in Da Nang. It would cause additional difficulties to the stranded visitors if they were unable to return home."

The Health Ministry said Saturday up to 800,000 visitors to Da Nang had left for other parts of the country since July 1.

Covid-19 returned to the community on July 25 after more than three months. Since then Vietnam has reported 174 domestic infections, including 120 cases in Da Nang.

Six Covid-19 patients had died since Friday, including three on Sunday alone.