Al Jazeera has uncovered evidence of government forces bombing villages surrounding the Yemeni capital, Sanaa.

At least 20 people have been killed and many families have been forced to live in caves as they fear dying in their homes in the next attack.

We investigated the story just as a UN team begins a 10-day mission in Yemen to investigate claims of human rights violations since the crackdown began on pro-democracy protesters.

Al Jazeera's Charles Stratford has this exclusive report on the bombed villages surrounding Sanaa.