LOS ANGELES: Music mogul Simon Cowell has alerted police after computers belonging to his record company Syco — part of Sony BMG — were hacked into. An early version of the British singer’s hotly-anticipated collaboration with Justin Timberlake appeared online. The single, called Don’t Let Me Down, was being considered as the first release from Leona’s second album — a follow-up to her 2007 smash hit Spirit. “