The Bonanza Creek Ranch in Santa Fe, N.M., 1n Oct. 2021. Jae C. Hong/Associated Press, file

New Mexico prosecutors are investigating whether the gun Alec Baldwin was handling when it went off and killed “Rust” cinematographer Halyna Hutchins might have been intentionally modified.

“The modification appears to be related to the notches on the internal portion of the hammer for full cock, half cock, and quarter cock positions,” prosecutors wrote in court documents filed this week, which asked the judge to authorize transferring the .45 Long Colt revolver, ammunition and other evidence collected from the film set to a ballistics expert for forensic testing. “It appears that these notches may have been partially removed or ground down so that they are less prominent.”

A photo of Halyna Hutchins during a vigil in her honor in Albuquerque, N.M., on Oct. 23, 2021. Andres Leighton/Associated Press

The development comes a month after prosecutors dropped the criminal case against Baldwin in Hutchins’s October 2021 death. Citing unnamed sources, the Los Angeles Times reported at the time that prosecutors had recently learned about possible modifications to the gun.

Charges of involuntary manslaughter were initially brought against Baldwin and “Rust” armorer Hannah Gutierrez-Reed in late January, with prosecutors alleging that they failed to follow several safety measures. Both pleaded not guilty.

But parts of the prosecution began to collapse. The Santa Fe district attorney’s office reduced the charges a month later, lessening the potential jail time. It dropped them all together for Baldwin in April.

The criminal case against Gutierrez-Reed is ongoing. The armorer is suing the movie’s ammunition supplier for allegedly providing live ammunition to the film set.

According to court documents, Gutierrez-Reed’s attorney, Jason Bowles, has no opposition to the prosecutors’ motion to transfer the gun. If it is found to have been modified, it could bolster Baldwin’s contention that he never pulled the trigger when it discharged, despite FBI tests and expert skepticism claiming otherwise.

The bullet struck two people on set with Baldwin during a rehearsal for the western film, killing Hutchins and wounding director Joel Souza.

Special prosecutors Kari T. Morrissey and Jason J. Lewis joined the case in March after district attorney Mary Carmack-Altwies stepped down.

While it remains uncertain whether a new case could be brought against Baldwin, he faces other legal challenges.

On Feb. 9, Hutchins’s family in Ukraine filed a lawsuit against him and others involved in the production, alleging battery, intentional infliction of emotional distress, negligence, and loss of consortium, which refers to the impact of Hutchins’s relationships caused by her death. Three former crew members sued Baldwin and the film’s producers the same month, asking for damages for “blast injuries” they say they suffered when the gun fired.

In a counterclaim he filed for a previous lawsuit in October, Baldwin is suing Gutierrez-Reed and others associated with the film for giving him the loaded gun that killed Hutchins. The suit “seeks to clear his name” and hold the defendants “accountable for their misconduct.”

“Rust” filming resumed in April, the same day prosecutors said charges against Baldwin would be dropped. Production moved from its original location in New Mexico to a ranch in Montana.

Baldwin posted a selfie to Instagram this week to celebrate the last day of filming, after shaving off the beard he grew for the Western.