TOKYO — Japan confirmed a new variant of COVID-19, and an infection cluster emerged at a Tokyo immigration facility, presenting new challenges as the country tries to overcome a third wave of the pandemic.

The new variant has been found in 91 cases in the Kanto area of eastern Japan and in two cases at airports, Chief Cabinet Secretary Katsunobu Kato told reporters Friday.

Japan has reported 151 cases of variants from Britain, South Africa and Brazil, according to the health ministry.

Meanwhile, five staff and 39 foreign detainees at a Tokyo immigration facility have tested positive for COVID-19

All 130 detainees at the facility have been tested for the virus, according to a spokesperson for the Tokyo Regional Immigration Bureau

None of the cases is serious, and all infected detainees remain quarantined from others