In pictures: Rituals of conversion to Zoroastrianism

Iraqi Kurdish Zoroastrian take part in a ritual ceremony in an ancient ruined temple of the Zoroastrian religion in the Iraqi Kurdish town of Darbandikhan

Zoroastrianism was founded in ancient Iran some 3,500 years ago, gaining followers as far afield as India. It was the official religion of the powerful Persian empire for thousands of years, but the assassination of the final Zoroastrian king in 650 and the rise of Islam sent it into a long demise.

High priest and his assistants wear white clothes representing purity. A cord knotted three times around waist symbolise the faith's core values of good words, good thoughts and good deeds.

Priest Qadrok performs ceremonies every week to welcome new converts. The religion only gained official recognition by regional authorities in 2015, but since then, three new temples have opened

The Faravahar worn by the priest is an ancient symbol of the Zoroastrian faith. It depicts a bearded man with one hand reaching forward. He stands above a pair of wings that are outstretched from a circle representing eternity. Fire is another important symbol of Zoroastrianism, as it represents light, warmth and has purifying powers.

A newcomer raises her hand and swear to abide by the three values of Zoroastrianism and to protect nature, respecting water, air, fire, earth, animals and humans.