Horrifying surveillance footage captured Idaho In-N-Out gunman Chad Williams’ every move while carrying out the deadly rampage that left three dead and several others wounded.

The video, released by the Twin Falls Police Department Friday, starts off by showing Williams, 24, driving up in a white Honda Civic to the drive-thru’s payment window.

After he’s seen rolling down his car window, the clip briefly stalls and blurs while a narrator explains that, in that moment, Williams pulled out a gun and struck In-N-Out employee Ashley Garibay, who later succumbed to her injuries.

Follow the latest on the mass shooting at an In-N-Out in Idaho:

The car then moves a few feet forward before the video pans to show Williams, visibly toting a black handgun, walking toward the drive-thru’s second window – where he then fatally shoots the second victim, 59-year-old Christopher Claunch, who was inside another car, according to the narrator.

At that moment, a former police officer who was nearby starts running toward the gunman, the heart-racing video shows.

This is a developing story. Please check back for updates.