The Hindu festival that turned deadly in northern India on Wednesday is a religious gathering with deep spiritual meaning for devotees who come by the millions to take a cleansing dip in waters they consider sacred.

Officials had been preparing for months for the world’s largest religious festival, with around 400 million Hindu pilgrims expected to take part

Witnesses described a mass of people rushing to take a pre-dawn dip at the confluence of the three sacred rivers.

A senior police officer said at least 30 people died as a crowd panicked at the Hindu Kumbh Mela mega-festival in the northern city of Prayagraj.

People were trampled as pilgrims at the Maha Kumbh Mela, one of the world’s biggest gatherings, gathered where the Ganges and Yamuna Rivers meet.