APPLETON, Wis. -- Dramatic bodycamera footage released by Appleton police in Wisconsin shows the moments leading up to a fatal shooting of a firefighter in May.The Outagamie County District Attorney said two Appleton police officers were justified in their shooting of Ruben Houston last month, reported WBAY. The announcement comes after a thorough investigation into the incident outside valley transit.The shooting also left a firefighter dead, a police officer injured, and an innocent bystander with gunshot wounds.According to investigators, Houston opened fire on first responders after they came to his aid when he was found unresponsive on a Lamers transit bus.Body cam footage from Sergeant Christopher Biese, on the bus, shows paramedics tending to Houston who was being treated for an opioid overdose by giving him two shots of Narcan.Houston was then able to walk himself off of the bus where police officers and paramedics tried to talk him into seeking additional medical help but he continued to refuse.Sgt. Biese: "Do you have any weapons on you?"Houston: "No sir."Sgt. Biese: "You have a bulge on your right side."Houston: "That's my phone."Sgt. Biese: "Don't reach for anything. Can I pat you down real quick?"Houston: "No, look man, I have a problem with officers touching me. I get nervous and stuff."It was just moments later, also caught on body cam, that Houston grabbed what has now been identified as a 380 semi-automatic weapon and fired two shots.Sgt. Biese and Officer Paul Christensen are the two who fired shots back at Houston.With Houston wounded and the shooting over, officers were able to take him into custody, where he later died at a local hospital.One of Houston's shots struck Officer Christensen and firefighter Mitch Llundgaard, who died from his injuries.Authorities believe Brittany Schowalter, who was used by Houston as a human shield was struck by the officer's gunfire.