SINGAPORE - What do you get when you cross the rich culture and hard-hitting strikes found in Muay Thai, with the ferocity of bare-knuckle boxing? Lethwei, the Burmese martial art with roots as far back as the second century.

Known also as "the art of nine limbs" - exponents are permitted to use their fists, elbows, knees, feet and head - the sport is considered one of the most brutal forms of martial arts.