Millions of devout Hindus led by naked ascetics with ash smeared on their bodies plunged into the frigid waters of India's holy Ganges River on Monday in a ritual they believe can wash away their sins.

The ceremony in the northern city of Allahabad took place on the most auspicious day of the Kumbh Mela, or Pitcher Festival, one of the world's largest religious gatherings that lasts 55 days. The festival continues until March 10.

Top festival official Mani Prasad Mishra said nearly 3 million people had bathed by late morning and 11 million were expected to enter the frigid water by the day's end.

Over 110 million people are expected to take a dip at the Sangam, the place where three rivers — the Ganges, the Yamuna and the mythical Saraswati — come together at the edge of this North Indian city. There are six auspicious bathing days, decided by the alignment of stars, when the Hindu devout bathe to wash away their sins and free themselves from the cycle of death and rebirth.

A sea of humanity assembled on the river bank as people waited patiently for their turn to step into the water. Men in underpants, women in saris and children — naked and clothed — chanted from Hindu scriptures as they walked into the icy-cold water.

'Long Live Ganges'

The bathing process was initiated by religious heads of different Hindu monasteries who reached the bathing points, called ghats, riding silver chariots. Some were carried on silver palanquins, accompanied by marching bands. Applause rose from tens of thousands of pilgrims waiting behind barricades as the religious heads set off the ceremony.

The heads of the monasteries threw flowers on the devotees as they shouted "har har gangey," or Long Live Ganges.

The biggest spectacle was that of the Naga sadhus, or ascetics, who raced to the river wearing only marigold garlands in a cacophony of religious chants.

About 50,000 policemen have been deployed to keep order at the festival, fearing everything from terrorist attacks to the ever-present danger of stampedes of pilgrims. Several squads policemen on horseback regulated the flow of pilgrims to and from the bathing ghats.

According to Hindu mythology, the Kumbh Mela celebrates the victory of gods over demons in a furious battle over a nectar that would give them immortality.

As one of the gods fled with a pitcher of the nectar across the skies, it spilled on four Indian towns- Allahabad, Nasik, Ujjain and Haridwar. The Kumbh Mela is organized four times every 12 years in those towns. Hindus believe that sins accumulated in past and current lives require them to continue the cycle of death and rebirth until they are cleansed. If they bathe at Ganges on the most auspicious day of the festival, believers say they can rid themselves of their sins.

Tens of thousands of pilgrims slept the night on the vast festival grounds in more than 1 million tents — green, blue, and brown — erected all over, while many huddled together under trees. Some 20,000 makeshift toilets have been have been erected, while 10,000 sweepers have been deployed to keep this make-shift tent town clean.