WATCH: Leftist Protester Calls Black Boston Cop ‘Stupid-Ass Black Bitch; You’re Supposed to Be on Our Side’

Shocking video has captured the moment a black left-wing activist, crashing a planned free speech rally in downtown Boston on Saturday, called a black police officer a “stupid-ass black bitch” for failing to be “on our side.”

The video sees black clad activists, including members of left-wing groups such as Antifa and Black Lives Matter, clashing with riot gear-wearing police officers.

The short video, recorded by reporter Philip Crowther sees leftist activists cursing at cops, throwing bottles of urine, spitting, and shouting racial slurs.

“You stupid-a** bitch. I’ll fucking spit on you, bitch. You stupid-a** black bitch. You’re supposed to be on our side!” screamed one black activist to a black police officer.

WARNING: Strong language

President Donald Trump praised the few hundred free speech protesters in Boston on Saturday, who had peacefully rallied before an estimated 40,000 leftist activists descended on the city of Boston.

“Our great country has been divided for decades. Sometimes you need protest in order to heal, & we will heal, & be stronger than ever before!” Trump wrote on Twitter.

The president also praised the Boston mayor and law enforcement officials for quickly quelling the violence that broke out.

“Police are looking tough and smart! Thank you,” Trump wrote. Some 27 arrests were made Saturday, according to the Boston Police Department. The Boston Police commissioner confirmed that “bottles of urine” and other items were thrown at the police officers.