A fire at a drug rehabilitation clinic in central Mexico left 12 people dead and several others injured, according to officials from Guanajuato state’s prosecutor’s office.The cause of the blaze, which broke out over the weekend, remains under investigation. However, fears are growing that it may be linked to criminal gang activity. Drug cartels operating in the region have previously targeted such clinics in brutal attempts to forcibly recruit patients into their ranks, AFP reported.Experts are gathering evidence and interviewing witnesses to uncover “the reasons for the tragic incident,” a statement released on Sunday said.This is not the first time a rehabilitation centre has come under attack. In April, gunmen stormed a similar facility in the troubled state of Sinaloa, killing at least nine people. Officials believe cartels often execute patients who refuse to join them.Mexico has been grappling with widespread criminal violence since the government launched a controversial war on drugs in 2006. Since then, nearly 480,000 people have been killed and around 120,000 remain missing, according to official figures.