The Indian authorities launched an investigation after an internal government report concluded that some private agencies responsible for coronavirus testing on pilgrims at a sprawling Hindu festival forged at least 100,000 results.

The festival, Kumbh Mela, which ran throughout April, is widely believed to be responsible for a coronavirus surge in many parts of India, as the pilgrims returning from the festival tested positive days after returning to their villages.

The festival drew millions of faithful to the town of Haridwar on the banks of the river Ganges in the northern state of Uttarakhand.