The incident happened on the set of "Rust" in New Mexico where Baldwin is playing the lead in a 19th-century western.
Actor Alec Baldwin has fired a prop gun on a movie set in New Mexico, killing cinematographer Halyna Hutchins and wounding director Joel Souza.
The incident occurred on the set of the independent feature film "Rust'', on Thursday, the Santa Fe County Sheriff's office said in a statement.
"The sheriff's office confirms that two individuals were shot on the set of Rust. Halyna Hutchins, 42, director of photography, and Joel Souza, 48, director, were shot when a prop firearm was discharged by Alec Baldwin, 68, producer and actor," the police said in a statement.
According to authorities, Hutchins was transported by helicopter to University of New Mexico Hospital, where she was pronounced dead, while Souza was taken by ambulance to Christus St Vincent Regional Medical center to undergo treatment for his injuries.
It was not immediately known how serious Souza's injuries were.
A Variety report said the shooting occurred at the Bonanza Creek Ranch, a production location south of Santa Fe.
A spokesperson from the production told The Hollywood Reporter the "accident" involved the misfire of a prop gun with blanks.
No charges have yet been filed in regard to the incident, said the police, adding they are investigating the shooting.
Baldwin has been on television and in films since the 1980s.
He starred in a number of high profile movies, including in "The Hunt for Red October" and two iterations of the "Mission: Impossible" franchise, and has also voiced animated characters in hits like "The Boss Baby".
He garnered new fans with his long-running portrayal of Donald Trump on "Saturday Night Live", a character that irritated the former president, but won Baldwin a Primetime Emmy.