A Buddhist monk in Japan has completed a gruelling nine-day ritual, apparently without eating, drinking or sleeping, it's been reported.

During the endurance test known as "doiri", meaning "entrance to the hall", Kogen Kamahori of the Tendai sect chanted the mantra of the Buddhist deity Acala 100,000 times while denying himself food and drink, or even lying down, the Mainichi Daily News reports.

The sect believes that carrying out the doiri makes you the living incarnation of Acala, a powerful warrior "wisdom king" who protects the faithful, sometimes with a flaming sword.

Some 600 people gathered to greet the 41-year-old as he emerged wearing a white robe at a training facility on Mount Hiei, a holy mountain in the south of Japan's main island. He's the first person to complete the test in eight years, and only the 13th since 1945, the paper says.

The doiri forms a part of a seven-year training programme known as the 1,000-day walk, in which a monk must circumnavigate the mountain on foot on 1,000 non-consecutive days in order to achieve enlightenment, Kyodo News Service says. Kamahori, who started the programme in 2011 and is chief monk at a temple in the Japanese city of Otsu, still has another two years of his 40,000km (24,800 miles) trek to complete.