Hip hop mogul Russell Simmons demanded an apology from Bill Clinton after the former president clashed with Black Lives Matter protesters Thursday at a Hillary Clinton campaign rally in Philadelphia.

Black Lives Matter heckling Bill Clinton led the former president to fiercely defend his 1994 violent crime bill and Hillary’s past statements, where she called law-breaking “gangs of kids” “super predators.”

Simmons aired his grievances with Bill Clinton on Twitter Thursday night:

The small drug users who were diseased and locked away deserve it? Bill Clinton u owe the black community and black lives matter an apology — Russell Simmons (@UncleRUSH) April 8, 2016

Simmons is a very vocal defender and supporter of Black Lives Matter, who has marched and protested alongside the movement’s leaders. He also has ties to the driving force behind the nonprofit arm of the Black Lives Matter movement.

Bill Clinton isn’t the first prominent Democrat that Russel Simmons has scolded in defense of the anti-police group. Last June, Russell Simmons called New York City Mayor Bill de Blasio a “punk” and a “bitch” for defending New York Governor Andrew Cuomo and New York City police commissioner Bill Bratton’s tough stance on policing the city’s streets.

Follow Jerome Hudson on Twitter: @jeromeehudson