SHOOTER BALDWIN'S MOMENT OF TRUTH!

Cameras catch his reaction to gunshot victim's tragic death

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BOMBSHELL text messages and dramatic new footage show tragic cinematographer Halyna Hutchins fighting for her life on the set of "Rust" and Alec Baldwin's shock when he finds out she died as damning new evidence suggests negligence on the set!

The ill-fated cowboy flick plunged into disaster after Alec fired a live round from a prop gun, which hit director Joel Souza and Halyna, leading to the 42-year-old mom of one's death at a New Mexico hospital.

Dramatic bodycam footage released by the Santa Fe Sheriff's Department shows medics frantically pumping oxygen to Halyna, doing chest compressions and calling for an airlift.