The woman in charge of the gun fatally fired by Alec Baldwin on the set of Rust told US police she “didn’t really check it too much” immediately before the tragedy.

Hannah Gutierrez-Reed, armorer on the low-budget Western, spoke to investigators as they probed how live rounds ended up on the New Mexico state film set in October, leading to the death of Halyna Hutchins.

Cinematographer Hutchins was shot and killed as Baldwin rehearsed a scene in which he fires a gun at the camera.

According to an affidavit released on November 30, Gutierrez-Reed told police she had loaded the Colt 45 with five dummy rounds before a lunch break.

After lunch, the weapon was retrieved from a safe, and Gutierrez-Reed added a final round before handing it to another crew member. Moments later, she heard a gunshot from inside the set.

Gutierrez-Reed said she “didn’t really check it too much” because the weapon had been locked up at lunch.

“We had the gun the whole time before that, and nothing happened, and I wasn’t in there, and they weren’t even supposed to be pulling the hammer back,” she added.

Police seized more than 500 rounds of ammunition from the set, which they believed to be a mix of blanks, dummy rounds and some suspected live ammunition.

On November 30, investigators shared new information about the possible origin of live rounds.

Ammunition for the production came from multiple sources, including Seth Kenney, an Arizona state weapon rental supplier.

Kenney told investigators he may have passed “reloaded ammunition” to the Rust set which matched the logo on a cartridge suspected to have contained the live round that killed Halyna.

“Reloaded ammunition” refers to rounds that are assembled from component parts, not manufactured as complete live rounds.

Gutierrez-Reed’s father Thell Reed, a veteran armorer, said he had provided live ammo to Kenney on a previous film they worked on together that was “not factory made”, and which was never returned.

Prosecutors have refused to rule out criminal charges against any person involved with Rust, including Baldwin and Gutierrez-Reed.

The pair are also among those named in at least two civil lawsuits filed by other crew members.

Gutierrez-Reed has said she has “no idea” why live rounds were present, and her lawyers suggested an act of “sabotage” by disgruntled crew members may have caused the tragic shooting.

Reports have emerged of disquiet among staff over allegedly lax safety procedures, and Santa Fe county Sheriff Adan Mendoza has spoken of “complacency” on the New Mexico set.

But Baldwin has called the tragedy a “one in a trillion episode” and insisted Rust had a “well-oiled crew”.