LOS ANGELES (AP) — Los Angeles Police Chief Charlie Beck said Wednesday he has yet to see evidence that would justify one of his officers fatally shooting an unarmed homeless man near Venice Beach. Beck cautioned that his department's investigation was just underway but told reporters he was "very concerned" by the Tuesday night shooting that occurred as an officer struggled with the man on a block lined with bars and restaurants. "Any time an unarmed person is shot by a Los Angeles police officer, it takes extraordinary circumstances to justify that, and I have not seen those extraordinary circumstances at this point," Beck said. Department investigators have not interviewed the officer because he is on medication to treat a knee he hurt during the struggle. The officers were not wearing body cameras, but police have surveillance footage from nearby stores that shows the events, Beck said. The confrontation began late at night when two officers responded to a 911 call saying the man, believed to be in his 20s, had been arguing with a bouncer who would not let him into a bar and was hassling passersby, police said. The officers spoke to the man, who began walking away but then came back and began struggling with someone on the sidewalk, according to a police news release. The officers tried to detain the man, who was shot during the struggle, police said. The man died at a hospital.