A group of U.K.-based DJs has been arrested for using iTunes and stolen or fraudulent credit cards to boost their chart rankings and steal royalty fees. Metro.co.uk reports that the nine musicians are accused of providing 19 songs to US-based distributor Tunecore, which uploaded the songs to iTunes and Amazon for sale. Once online, the DJs then opened accounts with stolen or cloned U.S. and U.K. credit cards to purchase their albums, with Apple and…