MINNEAPOLIS (AP) — To the general public, the video of a white police officer in Minneapolis pressing his knee into the neck of a black man prone on the street, crying out for help until he finally stopped moving, was horrifying.

Four officers were fired a day after George Floyd’s death, a stunning and swift move by the Minneapolis chief with the mayor’s full backing.

The officers were dismissed soon after a bystander’s video taken outside a south Minneapolis grocery store Monday night showed an officer kneeling on the handcuffed man’s neck, even after he pleaded that he could not breathe and stopped moving.

The FBI and state law enforcement were investigating Floyd’s death, which immediately drew comparisons to the case of Eric Garner, an unarmed black man who died in 2014 in New York after he was placed in a chokehold by police and pleaded for his life, saying he could not breathe.

Part of that investigation will likely focus on the intent of the officers, whether they meant to harm Floyd or whether it was a death that happened in the course of police work.