Vandals tore down a Black Lives Matter banner and sign from two historic Black churches in downtown Washington and set the banner ablaze as night-time clashes between pro-Donald Trump supporters and counterdemonstrators erupted into violence and arrests.
Police said today that they were investigating the incidents at the Asbury United Methodist Church and Metropolitan AME Church as potential hate crimes, which one religious leader likened to a cross burning.
"This weekend, we saw forces of hate seeking to use destruction and intimidation to tear us apart," District of Columbia Mayor Muriel Bowser said. "We will not let that happen."
A video posted on Twitter showed a group of men appearing to take down a BLM sign at the Metropolitan AME Church as others in the crowd shout, "Whose streets? Our streets."
Another video showed people pouring an accelerant on a BLM banner and setting it ablaze in the street as others cheered and cursed antifa. Someone walks up about a minute later and uses a fire extinguisher to put out the flames.
"It pained me especially to see our name, Asbury, in flames," the Rev Dr Ianther Mills, the senior pastor at Asbury church said in a statement. "For me it was reminiscent of cross burnings. Seeing this act on video made me both indignant and determined to fight the evil that has reared its ugly head."
"We will move forward, undaunted in our assurance that Black Lives Matter and we are obligated to continue to shout that truth without ceasing," she added.
Leaders of the Black Lives Matter organisation decried the attacks on the churches, partly faulting police for allowing white supremacists to "run rampant."
April Goggans, a lead organiser for Black Lives Matter's DC chapter, accused Bowser of "sitting silent and comfortable in your home as Trump send his goons in to brutalise your citizens." She said the mayor's statement was meaningless without action.
A spokesperson for DC police said that it was taking the offences seriously and actively investigating.
The incidents came following weekend rallies in support of Trump's baseless claims that he won a second term, which led to dozens of arrests, several stabbings and injuries to police officers.
Police in the District of Columbia said they arrested nearly 30 people for a variety of offenses, from assault to weapons possession and resisting arrests and rioting.
Four men were stabbed after a fight downtown, police said. At least one suspect, 29 year-old Phillip Johnson of Washington, was arrested on a charge of assault with a dangerous weapon.
Eight police officers were also injured during the demonstrations, officials said.