(CNN)Three separate investigations will probe the fatal shooting of a pedestrian on a Tennessee interstate by nine police officers.
Landon Eastep, 37, was killed after about 30 minutes of negotiations, during which traffic was halted along Interstate 65 near Nashville Thursday, authorities said.
Officers opened fire after he appeared "to adjust his stance and reach for what was later identified as a metal cylindrical object at his waist," the Tennessee Bureau of Investigation (TBI) said in a statement.
It was later determined not to be a firearm.
The leader of Nashville's Community Oversight Board will conduct one of three investigations into the shooting, the board said Friday night in a news release. Officers from the Metro Nashville Police Department (MNPD) and two other agencies were involved.
"The circumstances surround the death of Mr. Eastep by MNPD and other members of local law enforcement are gravely disturbing," the board said in a written statement. "Director [Jill] Fitcheard will initiate an independent investigation into the shooting."
The board is an independent body established by the metro government with the power to investigate allegations of police misconduct but does not have the direct ability to discipline officers or change policy. It was created in 2018 after being approved by voters.
An independent investigation of the incident had already been launched by the TBI on behalf of the Davidson County District Attorney's Office.
"Our team will work efficiently to gather relevant information at the scene, but the work may take some time," the TBI said.
And Metro Nashville Police chief John Drake ordered the department's training academy to review Thursday's police response. "I am saddened by any loss of life, and I send my condolences to the Eastep family," Chief Drake said in a written statement Friday.
The Nashville officer who fired the final two shots has been stripped of his police powers during the investigation, while five other officers have been reassigned to desk duties.
Standoff began on the shoulder of the highway
The standoff began around 2 p.m. Thursday. Eastep had been sitting on a guardrail on the shoulder of the interstate and a state trooper was attempting to get him to move off the highway, according to Metro Nashville Police Department spokesperson Don Aaron.
"The individual kind of pushed away from the trooper and produced a box cutter," Aaron said.
Officers from the Metro Nashville Police Department, Tennessee Highway Patrol and an off-duty Mount Juliet officer tried to de-escalate the situation, shutting down part of the interstate, when the man pulled out "a shiny, silver, cylindrical object" from his right pocket, Aaron said.
Body camera video released by the MNPD showed officers repeatedly asking Eastep to surrender. "Please, Landon. Please!" one officer is heard saying before the man is seen lunging with both hands together toward the officers, who open fire with a volley of shots. The man died on the scene, the TBI said.
Aaron said one officer had a Taser "on standby," but it was not used.
No officers were injured, according to the TBI, which is the lead agency investigating the incident.
Family and attorney react to shooting
An attorney for the family of Landon Eastep says they believe his fatal shooting by nine officers in Nashville was unjustified.
"This is what it looks like when you get trigger-happy," attorney Joy Kimbrough said at a news conference, pointing at Eastep's sobbing wife, Chelsea. "This is what it looks like when you don't know how to deal with mental health issues. This is the result."
Although he was in a restricted area of the interstate, Kimbrough said she saw no reason for officers to stop Eastep in the first place. "He was not obstructing traffic or impeding traffic," she said.
Kimbrough acknowledged Eastep had "bipolar issues," and Chelsea Eastep said her husband of less than a year seemed to be having problems Thursday. "He was agitated when he woke up, and he [went] out the door and took off walking. He left his phone at the house," Eastep said Friday.