Updated 5:30 p.m. | Posted 5 a.m.
State investigators said Tuesday that Jamar Clark was unarmed when he was shot Sunday by Minneapolis police, and the Hennepin County medical examiner concluded a gunshot to the head killed him.
Authorities also said that while they have some video from the confrontation, they don't yet have video capturing the entire incident.
There was no footage from police car dash cameras or body cameras, Minnesota Bureau of Criminal Apprehension Superintendent Drew Evans told reporters Tuesday.
Despite the demands of some protesters, Evans said videos of the incident will not be released now as they could taint interviews in the investigation.
Evans' comments and the medical examiner's conclusion came on the same day it was confirmed that federal authorities will conduct a civil rights investigation into the shooting of Clark, 24, in north Minneapolis.
Police say Clark had been interfering with paramedics who had been called to a birthday party to aid Clark's girlfriend. According to a BCA statement, the responding Minneapolis police officers believed the woman was an assault victim and that Clark was a suspect.
"At some point during an altercation that ensued between the officers and the individual, an officer discharged his weapon, striking the individual," the BCA said.
The shooting sparked protests after some witnesses said Clark was handcuffed when he was shot.
"We're still ongoing as to exactly how the handcuffs came into this scene," Evans said Tuesday. "There was handcuffs at the scene at the time and we're still examining whether or not they were on Mr. Clark or whether or not they were just fallen at the scene. That's what we're trying to ascertain."
Evans said no weapons were found at the scene beyond those of the officers.
As news of the shooting spread, the reaction from the group Black Lives Matter Minneapolis was swift.
On Sunday, hundreds of people marched several blocks down Plymouth Avenue North from the scene of the shooting to the Minneapolis Police Department's 4th Precinct headquarters. They hoisted a banner over the entrance and set up a tent, saying they'd stay until their demands are met.
On Monday night, several hundred people gathered for another rally outside the police station. Adja Gildersleve with Black Lives Matter Minneapolis called for the release any video of the incident that security cameras near the scene may have captured.
"It's not good for them to be having the footage for this long. And so that's a priority to us," she said. "We would also like to see the officer indicted and prosecuted."
Protesters made their way back down Plymouth Avenue and by 7 p.m. they were on the westbound lanes of Interstate 94. With traffic on the busy interstate at a standstill, state troopers directed vehicles down a grassy embankment to an off-ramp.
Authorities ultimately arrested 42 people for the I-94 shutdown.
Minneapolis Police Chief Janee Harteau told MPR News that the U.S. Justice Department agreed to investigate the matter at the request of Mayor Betsy Hodges, who said the federal presence would promote transparency and community trust.
Harteau on Tuesday said she welcomed the scrutiny.
Minneapolis officers are balancing people's First Amendment rights with the need to preserve the public's safety, she added.
"I tell my officers to stay focused, remain professional, be patient," she said. "This is not about us as individuals, this is about a profession. And we have to allow people to vent their frustration, but we also have to have the ability to do our job, and we have to do it with procedural justice."
Evans said the officers involved, who are on leave, will be named after they are interviewed in the next day or two.
Evans said there was video from the ambulance rig that was on scene as well as from a stationed mobile police camera in the area, from public housing authority cameras and from individuals that recorded on cell phone video.
He said the BCA is also working to get video from the Elks Club building across the street from where the shooting happened.
These investigations usually take two to four months, Evans said, but the BCA has given this case top priority.
Correction (Nov. 17, 2015): An earlier version of this story incorrectly reported the total number of people arrested during the I-94 protest.
MPR News reporters Jon Collins, Tim Nelson, Tim Pugmire and Doualy Xaykaothao contributed to this report.