Indian authorities have ordered a probe into the stampede at the Maha Kumbh Mela Hindu festival that killed dozens of devotees on Wednesday as millions gathered for a "holy dip" in sacred river waters as part of the six-week event,

At least 17 people were killed and many more injured in a stampede at India's Maha Kumbh festival, the world's largest religious gathering, a doctor at a government hospital said, as tens of thousands of pilgrims rushed to dip in sacred river waters during the Hindu event.

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.