Los Angeles - Los Angeles police officers acted within department policy when they fatally shot an 18-year-old man last year, whose death sparked a series of protests across the city, the police department's civilian oversight panel ruled on Tuesday.The determination from the Los Angeles Police Commission found the officers involved in the October 2016 shooting death of Carnell Snell jnr were justified in using deadly force. But the panel faulted the tactics used by the officers.Three people were arrested on Tuesday after several activists began protesting at the panel's weekly meeting.Snell was shot after officers tried to pull over a car he was in because it had paper license plates that didn't match the year of the vehicle. Snell jumped out and ran, and a chase followed, police said.After the shooting, activists and angry residents criticised police and dismissed the police department's account that Snell had been armed. The outcry led the city's police chief, Charlie Beck, to take the unusual step of publicly disclosing video showing Snell holding the gun.Los Angeles police typically release video of police shootings only after being ordered to do so by a judge.The surveillance video released by police showed Snell crouching behind an SUV parked at a strip mall and pulling a gun from the waistband of his sweatpants, but the footage failed to capture him when officers say he twice turned toward them holding the loaded semi-automatic handgun.Officers fired three shots that missed Snell, who then climbed a fence and turned again toward the officers while holding the gun, police said. Police fired three more times, hitting Snell in the torso and knee and killing him.The union that represents Los Angeles police officers commended the oversight panel for making "the correct ruling on this justified use of force"."When an armed suspect points a gun at a police officer, that officer must act to protect themselves and members of the public," said Craig Lally, the president of the Los Angeles Police Protective League.The shooting set off a series of Black Lives Matter protests across the city, including at the home of Mayor Eric Garcetti. Activists routinely mention Snell's death at weekly police commission meetings as they decry police misconduct.Three people who protested at Tuesday's police commission meeting were arrested on suspicion of obstructing a public officer, said Officer Drake Madison, a police spokesperson.After protesters refused to sit down and chanted during the meeting, the commissioners left the room and police ordered everyone out of the meeting. Several people refused to leave and a video posted on Twitter showed officers handcuffing Melina Abdullah, a Black Lives Matter organiser and professor at California State University, Los Angeles, and leading her out of the room.Police said they could not immediately provide the names of those arrested.