Update: 5:06 pm. Monday.
The Knox County Sheriff's Office released video of the accidental shooting.
The gun was discharged five seconds into the video, and you can see the reaction of the officers after the shot is fired. Officer James Blankenship who fired his weapon is on the far right of the screen.
The Tennessee Highway Patrol car seen in the video was dropping off a prisoner and was not involved in the incident.
Update 3:18 p.m. Monday
The deputy, who accidently fired his gun in the Knox County Detention Facility, resigned Monday shortly before noon.
In a letter to Sheriff J.J. Jones, James Blankenship, 39, wrote that he's resigning for personal reasons.
On Friday, Blankenship accidently fired a bullet into the pavement causing shrapnel to fly up and hit officers Kevin Potter, Patrick York and Marty Cruze.
Crews drove Porter to UT Medical Center where he was treated and released for a leg wound. York and Cruze were treated in the jail's medical unit. Blakenship was also taken to UT Medical Center where he was treated and released for chest pains.
According to the Knox County Sheriff's website, Blakenship's personal file shows that he was written up and counseled by a supervisor in August 2005 for leaving his weapon, two magazines, a knife, and cell phone in an unsecured gun locker in the jail.
The Office of Professional Standards and the Major Crimes Unit are still investigating the incident.
(WBIR-Knox County) A spokesperson with the Knox County Sheriff's Department says an officer at the Detention Center in East Knox County accidentally discharged his gun injuring three fellow officers Friday night.
According to the sheriff's website, a bullet from Officer James Blankenship's gun fired into the pavement causing shrapnel to strike three other officers.
This happened around 10:30 p.m.One was taken to UT Medical Center to be treated for a minor leg wound. He was released. The other two were treated at the jail.
The sheriff's spokesperson says Blakenship was taken to UT Medical Center to be treated for chest pains. He is at fault according to the preliminary investigation.
The website states that Blankenship is on paid administrative leave for the remainder of the investigation.