Grey’s Anatomy star and activist Jesse Williams, who last month mourned the deaths of Eric Garner, Mike Brown, and Tamir Rice during an impassioned speech at the BET Awards, is now commenting on the death of Alton Sterling.

The 37-year-old, who was armed, according to the Associated Press, was shot to death by police at a Louisiana store after it was reported to 911 that someone near the store was threatening them with a gun (the Justice Department will investigate the shooting). In a series of three tweets after news of Sterling’s death broke, Williams challenged his followers to “provide a list of Infractions Punishable by Spontaneous Public execution.”

“In the interest of time, would ye noble patriots please provide a list of infractions punishable by spontaneous public execution? Thanks!” he wrote. “Upon receipt of this list, we’ll return to our quarters and study up, eager to enjoy freedoms of white mass murders. #LIFEHACK.” He then added, “You chumps will NEVER provide this list… We see through you.”

Williams made a similar point in his BET Awards speech: “Now, what we’ve been doing is looking at the data and we know that police somehow manage to deescalate, disarm, and not kill white people everyday,” he said. “So what’s going to happen is we are going to have equal rights and justice in our own country or we will restructure their function and ours.”

“We’ve been floating this country on credit for centuries,” he continued, “and we’re done watching and waiting while this invention called whiteness uses and abuses us, burying black people out of sight and out of mind while extracting our culture, our dollars, our entertainment like oil – black gold, ghettoizing and demeaning our creations then stealing them, gentrifying our genius and then trying us on like costumes before discarding our bodies like rinds of strange fruit. The thing is though — the thing is that just because we’re magic doesn’t mean we’re not real.”

Williams wasn’t the only celebrity outraged by Sterling’s death – see more responses below, and read more about the shooting, which the Justice Department is set to investigate, here.