Kevin Frayer / AP

Hindu holy man Baba Sanjay poses before and after he had his head and face shaved as part of an initiation ritual where he was to become a Naga Sadhu.

Kevin Frayer, a photographer with The Associated Press, took a series of photos of Hindu holy men before and after they had their beards and hair shaved off as part of the initiation ritual to become Naga Sadhus — naked holy men — at the Maha Kumbh Festival in Allahabad, India.

The initiation of new Naga Sadhus can only be performed at the Kumbh Mela, which occurs once every 12 years and sees millions of devotees converging at the confluence of three holy rivers: the Ganges, the Yamuna and the mythical Saraswati.

Editor's note: Photos taken on Feb. 13, 2013 and made available to NBC News today.

Kevin Frayer / AP

Baba Ramshwal.

Kevin Frayer / AP

Brihaspst Giri.

Kevin Frayer / AP

Baba Vinod.

Kevin Frayer / AP

Baba Giri.

GRAPHIC WARNING: This post contains images which some viewers may find disturbing.

Kevin Frayer / AP

An Indian woman weeps as she watches from a staircase as rescue workers tend to the bodies of those killed in a stampede on a railway platform at the main railway station in Allahabad, India, Feb. 10,

At least 18 people were killed in a stampede in the Indian city of Allahabad on Sunday as Hindus returned from a river dip at the world's largest religious festival.

 An overcrowded railway station footbridge buckled and a railing collapsed, sending some people slipping down the stairs and triggering the stampede, a top state government official told Reuters, not wishing to be quoted by name.

-- Reported by Reuters

Full story: At least 18 killed during India festival stampede

Kevin Frayer / AP

An Indian man weeps as he and other family members mourn next to the body of a relative who was killed.

Kevin Frayer / AP

Indian police carry the body of a pilgrim who was killed.

Manan Vatsyayana / AFP - Getty Images

A woman lies on a bed at the Railway Hospital in Allahabad after being injured.

Saurabh Das / AP

Thousands of people crowd a platform waiting for trains to take them back home after visiting the Maha Kumbh festival in Allahabad, India.