<p>X Factor winners Little Mix have become the first British girl group to debut in the US top five - beating even the Spice Girls.</p><p>The quartet shot into the Billboard chart at number four after selling 50,000 copies of their first release DNA.</p><p>And they were applauded for their achievement by X Factor boss Simon Cowell, who sent an online message saying: "Congratulations Little Mix. Very proud of you."</p><p>The album has sold more than two million copies around the world and their team prepared for their US assault by mobilising their fanbase online and making personal appearances ahead of the release.</p><p><a href="http://www.belfasttelegraph.co.uk/entertainment/news/little-mix-eclipse-spice-girls-feat-29323674.html">Keep reading...</a></p>