Naked Madonna photo 'sells for $37,500'

A nude photograph of Madonna has sold at a New York auction for $37,500 (£26,100), more than double its original estimate.

The portrait was taken in 1979 by American photographer Lee Friedlander when Madonna was a dancer in her early twenties.

Christie's head of photography Matthieu Humery said that the full-frontal picture is "probably the most explicit" snap of Madonna from the session.

This picture and five others taken by Friedlander were originally sold to Playboy in the 1980s.

Madonna was reportedly paid $25 for the session and Friedlander described the future popstar as "very confident" and "a street-wise girl".

An image by Helmut Newton of Madonna in a short red dress with a man kneeling next to her sold at the same auction for $18,750.

Earlier this week, the singer's ex-husband Guy Ritchie was said to be "shocked" by new pictures of her posing provocatively with model Jesus Luz.