Japan has once again tightened quarantine measures for arrivals from countries affected by a coronavirus variant first detected in India.

People entering Japan from India and several other countries from Friday will have to self-isolate at government-designated facilities for 10 days. Beginning the same day, travelers from several other countries will be required to quarantine for three days at facility picked by the government, provide updates to authorities and undergo additional tests.

The recent moves are part of a crackdown on the spread of the “double mutant” coronavirus variant, which was found in India last year and has already made its way to Japan.