Japan's health ministry says four people who arrived at Tokyo's Haneda Airport earlier this month were infected with a coronavirus variant different from those found in Britain and South Africa.
The ministry says the four people are in their teens to their 40s and all of them had stayed in the state of Amazonas in Brazil.
They were found to be infected with the coronavirus at Haneda on January 2. The National Institute of Infectious Diseases analyzed their samples and found the virus is a new strain.
This is the first time this particular coronavirus variant has been detected in airport quarantine checks in Japan.