Twitter is "the source of all evil and devastation", the mufti saidTwitter is nothing more than "a source of lies" and evil, Saudi Arabia's top Muslim cleric said, in comments that sparked lively debate Tuesday on the microblogging site. "If it were used correctly, it could be of real benefit, but unfortunately it's exploited for trivial matters," Sheikh Abdul Aziz al-Sheikh said on his "Fatwa" television show broadcast late Monday.