Ten million Hindu pilgrims led by hundreds of ash-covered, naked holy men streamed into the sacred waters of the river Ganges on Wednesday at the world's biggest religious festival.
The date, chosen by astrologers, is the "main royal bathing day" of the Kumbh Mela, a 104-day event held in India every three years that is a riot of colour and noise as well as a gigantic spectacle of religious piety.
Devotees assembled along a 15-kilometre (nine-mile) stretch of the Ganges for a dip in the river that they believe cleanses them of sin and frees them from the cycle of life and rebirth.
The highest-ranking holy men, the naked "naga sadhus", consider themselves spiritual guardians of the Hindu faith and fiercely defend their right to bathe at the most auspicious moment.
Arriving at the riverside in Haridwar city at a jog, they chanted joyfully and brandished golden tridents, swords and sticks before throwing marigold garlands in the river and then plunging in themselves.
Sadhus are ascetics or wandering monks who renounce normal life and often live alone in remote mountains and forests devoting themselves to meditation, but emerge to lead the Kumbh Mela bathing sessions.
"Everything is going very smoothly and there has been no problem with any unruly mobs," Ashok Sharma, a press spokesman for the event, told AFP. "More than one crore (10 million) people are bathing today."
But in one reported accident, two women pilgrims were killed after being run over by a speeding car carrying naga sadhus, the Press Trust of India news agency said, citing police.
Dozens of one-way footbridges criss-cross the Ganges around Haridwar and a massive police presence of 16,000 personnel was on hand to prevent crowd congestion that has triggered deadly stampedes in the past.
Hundreds were crushed to death underfoot in 1954 and dozens also died in 2003.
The festival rotates between four locations and this year is being held in the northern city of Haridwar, where huge temporary encampments have catered for the flow of faithful from across India.
"To bathe in the Ganges today gives me inexpressible happiness," said 45-year-old Raj Kuntal from Himachal Pradesh, emerging from the chilly, fast-flowing water.
"A group of 100 of us came here by bus, and we are all deeply moved by the experience of being part of this very holy event."
Festival officials say that as many as 40 million people had bathed since January 14 in the Ganges at Haridwar, which is thought to be especially sacred during the Kumbh Mela.
Family groups, often containing many elderly and frail relatives, walked to the riverbanks after travelling in packed trucks, buses and trains to the festival site, which covers 130 square kilometres (50 square miles).
The Mela attracts many of India's bewildering array of Hindu tribes, castes and creeds, making a striking spectacle for foreign tourists who tackle the massive throngs.
"It is confusing and chaotic and wonderful," said Peter Hans, 22, from Germany, who had been sleeping in the open. "I think it is safe because the atmosphere is happy in a calm way, but the police are severe with the crowds."
The Har Ki Pauri ghat ("bathing steps") where the naga sadhus bathe is the focal point of the festival, attracting a constant stream of devotees who strip to their underclothes before entering the water.
Bathers hold onto chains to avoid being swept downstream, and afterwards offer short prayers from the steps that lead down into the river.
Many take a few gulps of the holy water and fill plastic bottles to take away.
Haridwar is the spot where the Ganges is said to leave the Himalayan mountains and start its long tour across northern India to the Bay of Bengal.
According to Hindu mythology, the city is where a few drops from a pitcher containing the nectar of immortality fell during a fight between gods and demons.
Kumbh Mela means "Pitcher Festival" and other drops are believed to have fallen at Allahabad, Nasik and Ujjain - the three cities where the festival is also held.
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