A new -- and even more dangerous -- form of fentanyl has been identified in dozens of deaths on San Francisco streets last year. According to a new report from the SF Medical Examiner's office, it's called fluorofentanyl. MORE: SF DA files 800+ drug cases 1st year in office but blames judges for allowing dealers to go free It was found during examinations of 45 people who died of drug overdoses last year. The strain can be up to five times more powerful than prescribed fentanyl. The Medical Examiner's office said it did not know how many deaths this year...