Devotees marked the end of India's mass river bathing festival with prayers and rituals.

Dramatic drone footage shows worshippers taking their final bath on Wednesday, February 26, wrapping up the six-week Maha Kumbh Mela.

Authorities said that over the last 45 days, more than 620 million people attended the event to take a holy dip in the sacred river in Prayagraj, Uttar Pradesh.

The Maha Kumbh Mela is a major Hindu pilgrimage festival held every 12 years, where millions of devotees and tourists gather to bathe in the river, believing it cleanses sins and grants salvation.

This comes despite a recent report from the Central Pollution Control Board stating that some parts of the river failed to meet water quality standards for bathing due to high faecal coliform levels.

Faecal coliform is a group of bacteria found in the intestines of humans and animals. Their presence in water suggests contamination from human or animal waste.

Two separate incidents of chaos have also led to dozens of deaths and injuries.

While tragically, on the evening of February 15, thousands of devotees flocking to the festival caused a stampede that killed at least 20 people at a railway station in New Delhi.

Officials said 14 women and four children died when crowds tried to board packed carriages heading to the event.

Earlier, on January 29, millions had gathered at the Maha Kumbh Mela for a holy dip when disorder broke out around 1:30 am. Police confirmed that at least 30 devotees were killed and 60 others injured.