A vehicle drove through a group of police and National Guard troops at a demonstration in support of George Floyd in upstate New York, injuring at least two officers.
Video from the scene shows the vehicle accelerating through an intersection in Buffalo, almost 400 miles north-west of Manhattan, shortly after several officers apparently tackle a person on the street and handcuff that person.
Other officers are then seen tending to the injured officers on the sidewalk, while the vehicle drives off past a military vehicle on Buffalo’s east side.
The officers were taken to Erie County Medical Centre, where authorities said their condition was stable.
Meanwhile, police made unrelated arrests inside iconic department store Macy’s in Manhattan as violence and protests continued in streets across the country after Mr Floyd, an unarmed black man, died while in police custody.
The arrests came hours after US President Donald Trump threatened to deploy the military if state governors did not halt ongoing the ongoing violence.
Speaking in the White House Rose Garden, Mr Trump said: “First, we are ending the riots and lawlessness that has spread throughout our country. We will end it now.
“Today I have recommended to every governor to deploy the National Guard in sufficient numbers that we dominate the streets.
“If a city or state refuses to take the actions that are necessary to defend the life and property of their residents, then I will deploy the United States military and quickly solve the problem for them.”
There have been six straight days of unrest set off by the death of unarmed black man George Floyd in Minneapolis, with curfews now imposed in New York City and Los Angeles due to a coast-to-coast outpouring of rage over police killings of black people.