Tens of thousands of Hindu pilgrims have gathered in the northern Indian city of Prayagraj (formerly Allahabad) for a festival amid a massive surge in Covid-19 infections, BBC reports.
Devotees believe that bathing in the river Ganges during the Makar Sankranti festival would cleanse their sins.
A similar gathering had contributed to India's deadly second wave last year.
But the authorities in Uttar Pradesh state, where Prayagraj is located, have refused to ban this year's event.
TV footage on Friday showed crowds at the river bank as pilgrims offered prayers with little regard to social distancing. Hindi news channel ABP reported that more than 70% of the people were without masks.
A large tent city has sprung up on the river bank in the past few days to house the pilgrims and authorities say more than 5,000 policemen are being deployed to manage the crowds.
Chief Minister Yogi Adityanath has appealed to people to follow all necessary Covid protocols during the event, known as Magh Mela.
But infections were reported from the mela ground even before the start of the event.
Senior police official Rajeev Narayan Mishra told the BBC on Thursday that at least 38 police personnel on duty had tested positive, sparking fears that the festival could turn into an infection hotspot in the coming days.
In April last year, millions of pilgrims had gathered in the Himalayan town of Haridwar, in the neighbouring state of Uttarakhand, to participate in the Kumbh Mela festival even as several cities grappled with a severe shortage of oxygen and hospital beds.
Several of the pilgrims - who came from all parts of the country - tested positive after returning home, with epidemiologists describing the festival as a "super-spreader event".
This year, the authorities in Uttarakhand have banned devotees from taking a dip in the river during the festival.
The insistence of Uttar Pradesh to hold the Magh Mela festival has experts worried about the consequences it could have on public health.
India is in the midst of a third wave of the pandemic, believed to be fuelled by the Omicron variant of the coronavirus.
The country reported over 247,417 new infections on Thursday - the most since late May - driven by a steep rise in cases in big cities such as the capital, Delhi, and financial centre of Mumbai.
