Hindu pilgrims descended on the banks of the Ganges River Thursday, shrugging off COVID-19 risks for the start of the Kumbh Mela, a religious festival that regularly attracts millions.

India's severe outbreak - the second most coronavirus infections in the world, and more than 150,000 deaths - has not stopped devout Hindus from making the pilgrimage to Haridwar in northern India.

"The pandemic is a bit of a worry, but we are taking all precautions," said organizer Siddharth Chakrapani, who expected between 800,000 and a million people to attend on Thursday alone.

"I'm sure Maa Ganga will take care of their safety," he added, referring to the river considered holy by the faithful.

According to Hindu mythology, gods and demons fought a war over a sacred pitcher containing the nectar of immortality. Drops fell at four different locations, which now alternate as hosts for the immense gatherings.

Kumbh Mela is recognized as a piece of intangible cultural heritage by UNESCO, and its last edition - in Allahabad in 2019 - attracted around 55 million people over 48 days.

This year, beginning Thursday, Haridwar is the host, and several million people are expected to throng the holy city in Uttarakhand state over the coming seven weeks.

Taking a dip in the Ganges is considered a sacred rite by Hindus, who come from across India and beyond its borders to participate.

Holy men known as sadhus - boasting outrageous dreadlocks and smoking cannabis - are a regular feature at the Kumbh Mela, camping by the river and offering blessings to those who come for the holy immersion.

On Wednesday, the river's banks teemed with pilgrims and vendors while families laid out plastic sheets to put their belongings on while they took turns to plunge in the river.

This week brings several other religious festivals in India, including the Gangasagar in Kolkata where officials expect around 15,000 people.