Border forces in China’s Yunnan Province last Saturday handed over the eight men and 22 women to their counterparts in Lao Cai Province.
The workers, many of them ethnic H’Mong people, had reportedly crossed into China through open paths looking for jobs on banana and rubber farms in Yunnan since November last year.
When the Covid-19 pandemic began in December Chinese authorities sought to identify foreign workers to contain the spread of the virus and found these Vietnamese had entered illegally.
They placed them in detention for more than three months before sending them home.
At the Lao Cai border, the returnees had to make health declarations and were then sent to a quarantine center for 14 days.
Lao Cai has set up 13 quarantine centers.
Last month it received 500 workers returning from China, border authorities said. They went to that country legally, but had to return since Chinese factories have been laying off workers due to the impact of the pandemic.
China, where Covid-19 first broke out in Wuhan City last December before spreading to 211 other countries and territories around the world, has reported more than 82,000 cases of infection and 4,633 deaths.