New Mexico authorities said Wednesday they have recovered a lead projectile believed to have been fired from the gun used in the fatal movie-set shooting.

Investigators discussed their initial findings in the shooting in which actor Alec Baldwin fired a gun, killing a cinematographer and wounding the director.

Testing is being done to determine whether the lead projectile recovered from director Joel Souza’s shoulder was fired from the gun used by Baldwin.

Santa Fe County Sheriff Adan Mendoza said it’s too early to comment on whether any charges will be filed. He also noted that 500 rounds of ammunition - a mix of blanks, dummy rounds and live rounds - were found while searching the set.

The sheriff would not comment on how the rounds got on set.

Investigators said they will also be following up on reports that there were other incidents involving misfires with guns used on the set.

District Attorney Mary Carmack-Altwies said investigators can’t say whether it was negligence or by whom at this point.

Both the sheriff and district attorney said they will not rush to judgment and that more investigation is needed.

The shooting has baffled Hollywood professionals and prompted calls to better regulate firearms on sets or even ban them in the age of seamless computer-generated imagery. Court records say that an assistant director grabbed the gun from a cart and indicated the weapon was safe by yelling “cold gun.”

The film’s armorer, Hannah Gutierrez Reed, said she checked dummy bullets on the day of the shooting to ensure that none were “hot” rounds. She also told a detective that while the guns used for filming were locked up during a crew lunch break, ammunition was left on a cart unsecured, according to a search warrant released Wednesday ahead of the press conference.

Gutierrez Reed told a detective that no live ammo was ever kept on the set.

Assistant director David Halls, who handed the gun to Baldwin before the shooting, said Gutierrez Reed typically opened the hatch of the gun and spun the drum, though he couldn’t recall if she did that before the shooting. He said he only remembered seeing three rounds in the gun.

After the shooting, Halls took the gun to Gutierrez and said he saw five rounds in the gun, at least four of them were “dummy” rounds indicated by a hole on the side and a cap on the round. Halls said there was also a casing in the gun that did not have the cap and did not have the hole indicating it was a dummy.

“David advised the incident was not a deliberate act,” according to the warrant.

The warrant was issued Wednesday in order to search a truck that was used on the set.