Women known as “madams” have involved children as young as 13 in prostitution in Kenya, a BBC investigation has found. Two undercover investigators, posing as sex workers wanting to learn how to become madams, spent months infiltrating the sex trade in Maai Mahiu. Their secret filming reveals two different women who say they know it is illegal, and then introduce the investigators to underage girls in the sex industry. The BBC gave all its evidence to the Kenyan police in March - we believe the madams have moved location since then. The police said the women and young girls we filmed could not be traced - to date there have been no arrests. Tap the link in @BBCNews’s bio to hear more from the girls we spoke to. #BBCAfricaEye #BBCNews