Police investigators have maintained Alec Baldwin "pulled the trigger" on the prop firearm that fatally wounded cinematographer Halyna Hutchins on the set of Rust.
Last October, the 30 Rock actor's prop gun was accidentally discharged during a rehearsal for a scene in Santa Fe, New Mexico, killing Hutchins and wounding director Joel Souza.
While Baldwin alleged "the trigger wasn't pulled" during a TV special that aired in December, officials from the U.S. Federal Bureau of Investigation (FBI) have released a forensic report, obtained by ABC News on Friday, which rejected the 64-year-old's claim.
Following "accidental discharge testing," the FBI officers concluded that the gun "could not be made to fire without a pull of the trigger".
With the "hammer fully cocked", they also asserted that the firearm "could not be made to fire without a pull of the trigger while the working internal components were intact and functional".
Representatives for Baldwin and the producers of Rust have not yet commented on the findings of the report.
The incident is still being investigated by the Santa Fe County Sheriff's Office and no charges or arrests have been made.
The actor and Rust producers were named as defendants in a wrongful death lawsuit filed by the cinematographer's widower Matthew Hutchins in February.
Baldwin has consistently maintained his innocence and recently said he feels "very hopeful" that he won't be held criminally responsible.