Officials have identified the suspect in the mass shooting which occurred at an Idaho In-N-Out Burger as 24-year-old Chad Williams, leaving at least three people dead and seven injured.

Authorities revealed his identity during a press conference Sunday and confirm he is deceased from a self-inflicting gunshot wound. According to officials, investigators are continuing to look into the incident timeline, process evidence, and conduct interviews.

Waiting for your permission to load the Instagram Media.

As we previously reported ... the mayhem began Saturday afternoon at the burger joint in Twin Falls -- a city in southern Idaho -- where the gunman opened fire, officials said.

Twin Falls spokesperson, Josh Palmer, told TMZ ... police received a call of an active shooter and quickly responded, but the shooter had already exited the restaurant and fled the immediate area.

Waiting for your permission to load the Instagram Media.

A motorist filmed the shooter with a cell phone camera walking to a white car while carrying a long gun. The suspect opened the driver-side door and popped the trunk, then walked to the rear of the car and reached inside the trunk. Fearing the suspect might be reaching for another firearm, the motorist took off.

In-N-Out President Lynsi Snyder remembered the fallen employee and slammed the shooter as a "disgusting human who doesn't value the lives of others or his own."

Police were interviewing numerous witnesses and canvassing for video at retail shops near the crime scene. Investigators were also trying to identify the suspect and determine a motive. Palmer said there were no other shooters and the threat to the public was over.