Authorities have confirmed the suspect responsible for shooting six people at a FedEx facility in Georgia – a man a witness said looked "like Rambo" -- is dead from a self-inflicted gunshot wound.

The workplace shooting was reported at about 5:44 a.m., Tuesday, at the FedEx facility in Kennesaw, located about 30 miles northwest of Atlanta.

FedEx clerk Liza Aiken told WXIA-News that she saw the gunman prior to the shootings and he was dressed in black and camouflage.

"He had bullets strapped across his chest like Rambo, a huge assault rifle and he had a knife," Aiken said.

Authorities confirmed the gunman, who was found dead in the facility from a self-inflicted gunshot wound, was armed with a shotgun.

Investigators have yet to name the suspect or the victims, but have confirmed the suspect was a FedEx employee.

Three of the shooting victims are in critical condition. Authorities have released the age and sex of each victim. The three individuals in critical condition are a 22-year-old male, a 28-year-old male and a 52-year-old female. A 38-year-old male is in stable condition, a 19-year-old male is pending release from the hospital and a 42-year-old female has been treated and released.

"We can confirm that an incident occurred early Tuesday morning at a FedEx Ground facility in Kennesaw, Georgia," a company spokesman said in a statement. "Our thoughts and prayers are with those affected, and with their families and friends ... The situation is now stabilized and we are focused on the needs of our team members and cooperating with the law enforcement investigation of this tragedy."

Authorities are expected to release additional details later today.