According to police, an officer opened fire on a knife-wielding suspect after three taser deployments had no effect. PHILADELPHIA - Philadelphia police are releasing more information about an officer-involved shooting that left a suspect in critical condition on Wednesday.Shortly before 11 a.m., two uniformed officers in a marked patrol car responded to a call for a person armed with a knife on the 4700 block of Rorer Street.Police say the officers encountered the suspect, an unidentified Hispanic male approximately 45-years-old, at the top landing of the stairs armed with a knife.The male allegedly began to walk down the stairs towards the officers as the officers backed away while ordering the man to drop the knife.According to.