NEW YORK (AP) — A killer who strode up to a mobile police command post and put a bullet in an officer's head Wednesday had ranted in a Facebook video last September about law officers killing and abusing people and warned them to leave him alone or "we gonna do something.""I'm not playing, Mr. Officer. I don't care about 100 police watching this," 34-year-old ex-convict Alexander Bonds said, adding: "It's time for people to wisen up."Ten months later, Bonds went up to the RV-like command post in the Bronx and ambushed Officer Miosotis Familia, shooting her through the passenger side window as she wrote in her notebook around 12:30 a.m.Police Commissioner James O'Neill said Familia was "assassinated in an unprovoked attack on cops."Familia's partner frantically radioed for help, and officers caught up with Bonds about a block away and killed him in a hail of about 20 bullets when he pulled a stolen revolver, police said. He didn't get off a shot, authorities said.