The Holly Bobo murder trial continued into its fifth day Friday, bringing the testimony of still more witnesses in the case. Prosecutors heard additional details about the alleged murder weapon used to kill Bobo, while other testimony heard authorities from the Tennessee Bureau of Investigation admit they had made mistakes in the search for the 20-year-old.

Bobo went missing in 2011 from her family’s Tennessee home. The ensuing search for Bobo was the longest and costliest in the state’s history. A nursing student at the time, Bobo’s body was not uncovered until three years later, when her skull was found by a hunter in a wooded area. This week’s long-awaited trial accused Zach Adams of her rape, kidnapping and murder.

Earlier this year, the trial was delayed after authorities located a gun allegedly used to kill Bobo. Victor Dinsmore, the man who helped authorities find the gun, appeared to testify Friday morning. Dinsmore said he knew Adams and two other men charged in the murder, Jason Autry and Shayne Austin, back in 2011. At the time, Austin gave Dinsmore the gun in exchange for 12 morphine bills, Dinsmore said. He also said he ended up giving the gun to his wife because he was not allowed to own a firearm and was concerned about where it had come from.

“I was worried it had a body on it,” Dinsmore testified. “Meaning I was worried it had been used to kill someone.”

It remained unclear why it took six years for the gun to be located.

In other testimony Friday, Tennessee Bureau of Investigation Special Agent Brent Booth asserted that the organization made mistakes early on in the case. Agents neglected to read memos in enough detail and put priority on tips claiming Bobo was still alive instead of tips pointing the finger at Adams, Autry and Austin.

“The left hand didn’t know what the right was doing,” said Booth. “We didn’t realize what was there. Their alibis weren’t checked out.”

The trial’s fifth day followed a disturbing Thursday in court in which Autry, a key witness who was also charged in the case, testified about Bobo’s death and disposing of her body. Autry said Adams called him for help getting rid of the body. When the two men were in the car with Bobo’s body wrapped in a blanket, they realized she was still alive, Autry said.

“I see a foot moving and I hear a sound of distress coming out of the blanket,” said Autry. “At that time I walked to the door of the passenger side … and I told [Adams] ‘This f—— b—— is still alive. She’s heard my name called and me talking and all.’”

Once Adams realized she was still alive, Autry said, he pulled out a pistol and shot her. Adams himself has pleaded not guilty to all charges in the case and asserted his innocence throughout. Should he be convicted, he could face the death penalty.

Watch the trial live here.