Prosecutors had previously said it might never be clear how live rounds, which are not allowed on movie sets, got to the “Rust” set in New Mexico.

Charging documents had held that Hannah Gutierrez-Reed, who was working as chief weapons handler on her second film, was responsible for “allowing live ammunition on the set”, but not for bringing in the rounds.

In a June 8 court filing, special prosecutors Kari Morrissey and Jason Lewis cited “some evidence” to support the theory that defendant Gutierrez may have been responsible for introducing the live rounds on set.

“If this theory is confirmed, additional criminal charges may follow,” they said.

Gutierrez-Reed had four spent casings in her gun kit bag that appear to match live rounds found on the New Mexico set, prosecutors said in the filing.

Lawyer Jason Bowles, who represents Gutierrez-Reed, did not immediately respond to a request for comment.

Dave Halls, the first assistant director on “Rust”, pleaded in a deal with prosecutors to negligent use of a deadly weapon for his role in Hutchins’ death.

Charges against Baldwin were dropped after new evidence suggested the gun’s hammer might have been modified, causing it to misfire. Baldwin has said he did not pull the trigger.

Gutierrez-Reed is the only person now charged with Hutchins’ death, although prosecutors said they would decide within 60 days whether to file new charges against Baldwin.

Defence lawyer Bowles has previously said Gutierrez-Reed never bought nor had access to ammunition, the type of live round that killed Hutchins.

Gutierrez-Reed said she had loaded the live round into the “Peacemaker” revolver used by Baldwin thinking it was a dummy round.