Minneapolis mayor tries to calm city rocked by violence

Minneapolis Mayor Jacob Frey has called for calm following a second night of protests over the death of a black man in police custody.

Frey has asked the state's governor to activate the National Guard.

He said at a briefing Thursday that the conflict "is the result of so much built up anger and sadness that has been ingrained in our black community, not just because of five minutes of horror, but 400 years."

George Floyd died Monday after he was arrested and a police officer kneeled on his neck for several minutes during an encounter that a bystander captured on a cellphone camera.

Protests also spread to other U.S. cities.

Minneapolis police said Wednesday night's violence contrasted sharply with a mostly peaceful demonstration Tuesday afternoon at the street corner where Floyd died.

The U.S. Attorney's Office and the FBI in Minneapolis said Thursday they were conducting "a robust criminal investigation" into Floyd's death and making the case a priority. The announcement came a day after President Donald Trump tweeted that he had asked an investigation to be expedited.

The FBI had already announced that it would investigate whether Floyd's civil rights were violated.

The officer who kneeled on Floyd and three others were fired Tuesday. On Wednesday, the mayor called for him to be criminally charged.