The death toll from a stampede in a train station rose to 36 on Monday in a northern India city where millions of devotees had gathered for a Hindu festival that is one of the world's largest religious gatherings.

At least 36 other pilgrims were injured in the crush in the city of Allahabad, medical superintendent Dr. P. Padmakar of the main state-run hospital said. Padmakar said 23 of the dead were women.

Tens of thousands of people were in the city's main rail station waiting to board a train when railway officials announced a last-minute change in the platform, forcing people to rush there, eyewitnesses said.

They said police stopped the throng from crowding onto a footbridge and had to use batons to stop the crowds from surging forward.

"We heard an announcement that our train is coming on platform number 4 and when we started moving towards that platform through an overbridge, we were stopped. Then suddenly the police charged us with batons and the stampede started," passenger Shushanto Kumar Sen said.

"People started tumbling over one another and within no time I saw people, particularly women and children, being trampled over by others," Sen said.

The police, however, denied that they had used batons to control the crowd.

"It was simply a case of overcrowding. People were in a hurry to go back and there were not enough arrangements by the railway authorities," said Arun Kumar, a senior police officer.

India's railway minister Pawan Kumar Bansal said an inquiry has been ordered into what led to the stampede.

Indian television stations showed large crowds pushing and jostling at the train station as policemen struggled to restore order.

"There was complete chaos. There was no doctor or ambulance for at least two hours after the accident," an eyewitness told NDTV news channel.

An estimated 30 million Hindus were expected to take a dip at the Sangam, the confluence of the Ganges, the Yamuna and the Saraswati rivers on Sunday, one of the holiest bathing days of the Kumbh Mela, or Pitcher Festival. The festival lasts 55 days and is one of the world's largest religious gatherings.

The auspicious bathing days are decided by the alignment of stars, and the most dramatic feature of the festival is the Naga sadhus — ascetics with ash rubbed all over their bodies, wearing only marigold garlands — leaping joyfully into the holy waters.

According to Hindu mythology, the Kumbh Mela celebrates the victory of gods over demons in a furious battle over 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 held 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 the Ganges on the most auspicious day of the festival, believers say they can rid themselves of their sins.