A Louisiana police officer shot and killed a black man during a confrontation outside a convenience store, prompting hundreds to protest at the site where the man died.
An online video that surfaced purporting to show the killing of Alton Sterling, 37, of Baton Rouge, on Tuesday added to protesters' outrage.
The protest lasted into the night, with people chanting and holding up signs.
The Advocate reported the crowd that gathered late on Tuesday afternoon at the store where Mr Sterling died grew to more than 200 people.
They chanted "black lives matter" and "hands up don't shoot" and waved signs late into the night, according to the newspaper.
An autopsy shows Mr Sterling died of multiple gunshot wounds to the chest and back, East Baton Rouge parish coroner Dr William Clark said.
Officers responded to the incident at about 12.35am on Tuesday after an anonymous caller indicated a man selling music CDs and wearing a red shirt threatened him with a gun, Cpl L'Jean McKneely said.
Two officers responded and had an altercation with the man and one officer fatally shot the suspect, Cpl McKneely said. Both officers have been placed on administrative leave, which is standard department policy, he said.
The store's owner, Abdul Muflahi, said the first officer used a stun gun on Mr Sterling and the second officer tackled the man.
Mr Muflahi said that as Mr Sterling fought to get the officer off him, the first officer shot him "four to six times."
The owner said Mr Sterling did not have a gun in his hand at the time but he saw officers remove a gun from Mr Sterling's pocket after the shooting.
Cpl McKneely said he could not confirm Mr Muflahi's description of the event or any other details of the investigation.
Kimberly Lang said she purchased CDs from Mr Sterling occasionally and said he did not have a reputation for violence, according to a report.
Ms Lang said if Mr Sterling did have a gun on him it was probably because he feared being robbed while peddling his CDs late at night, not because he wanted to threaten anyone.