The mayor of Ferguson in Missouri has announced a series of measures in response to evidence of widespread racial discrimination by the American city's police force.
A United States Justice Department investigation into last year's police killing of Michael Brown, 18, has found a pattern of racial bias in the town's police, court and jail systems.
His death sparked nationwide protests over police treatment of minorities.
Mayor James Knowles said one police department employee had been sacked and two others placed on leave after being accused of sending racist emails.
"Department of Justice officials inform the city of Ferguson that a review of city emails uncovered explicit racial bias by three individuals who are employed by the city of Ferguson police department.
"This type of behaviour will not be tolerated in the Ferguson police department, or in any department in the city of Ferguson."
Mr Knowles said the department would increase the number of non-white officers and improve diversity training.
'Immediate, wholesale' action needed
US Attorney General Eric Holder said leaders in Ferguson, Missouri, must take "immediate, wholesale" action after a report of widespread racial bias in its law enforcement.
In what Mr Holder himself called a "searing" report, the justice department found a "disturbing and unconstitutional" pattern of abuse.
A separate investigation ended with no federal civil rights charges against former Ferguson police officer Darren Wilson, who killed Brown.
A Missouri grand jury also declined to charge him with murder in November.
"Michael Brown's death, though a tragedy, did not involve prosecutable conduct on the part of Officer Wilson," Mr Holder said in a statement at the justice department.
Mr Holder acknowledged the result of the investigation into Mr Wilson did not match up with expectations, and that was in part because of what the wider investigation found about the Ferguson police department and courts.
He described Ferguson as a community where officials used law enforcement to generate revenue and did so disproportionately against African-Americans because of racial bias.
"Amid a highly toxic environment, defined by mistrust and resentment, stoked by years of bad feelings, and spurred by illegal and misguided practices - it is not difficult to imagine how a single tragic incident set off the city of Ferguson like a powder keg," Mr Holder said.
"In a sense, members of the community may not have been responding only to a single isolated confrontation, but also to a pervasive, corrosive, and deeply unfortunate lack of trust."
Mr Holder identified several of the worst abuses found in the report, including a man arrested at gunpoint after he objected to a police officer accusing him of being a paedophile without probable cause. The man lost his job because of the arrest, the attorney general said.
The report also found black residents were disproportionately subject to baseless traffic stops and citations for infractions as petty as walking down the middle of the street.
The justice department also outlined their findings of explicit racial bias in the ranks - including emails that depicted President Obama has a chimpanzee, as well as many offensive stereotypes about black Americans.
The report noted public officials regularly made tickets and other minor violations "go away" for for white friends while some black residents spent nights in jail for non-payment of tickets.
Although some community perceptions around the death of Michael Brown may not have been accurate, Mr Holder said, "the climate that created them was all too real". He added: "Some of those protesters were right."
Mr Holder said that while the problems found in the report in Ferguson were "acute" they were "not confined to any one city, state, or geographic region".
The Department of Justice report was greeted with optimism by some.
"It's quite evident that change is coming down the pike. This is encouraging," said John Gaskin III, a St Louis community activist on Wednesday.
"It's so unfortunate that Michael Brown had to be killed. But in spite of that, I feel justice is coming."