The report, dated August 2017 and compiled by the Domestic Terrorism Analysis Unit, said: “The FBI assesses it is very likely Black Identity Extremist (BIE) perceptions of police brutality against African Americans spurred an increase in premeditated, retaliatory lethal violence against law enforcement and will very likely serve as justification for such violence.” Incidents of “alleged police abuse” have “continued to feed the resurgence in ideologically motivated, violent criminal activity within the BIE movement”.

The FBI’s dedicated surveillance of black activists follows a long history of the US government aggressively monitoring protest movements and working to disrupt civil rights groups, but the scrutiny of African Americans by a domestic terrorism unit was particularly alarming to some free speech campaigners.