Larry Copeland and Doug Stanglin

USA TODAY

KENNESAW, Ga. — A 19-year-old package handler decked out "Rambo-style," with an assault rifle and bullets strapped to his chest, opened fire on fellow employees at a FedEx facility in suburban Atlanta early Tuesday, wounding six people — one critically — before killing himself.

The man, dressed all in black, entered the 500,000-square-foot warehouse and began shooting at 5:54 a.m. ET, said Sgt. Dana Pierce of the Cobb County Police Department. The shooter was identified as Geddy Kramer.

Police found the suspect about three hours later dead of an apparent self-inflicted gunshot wound in the loading dock area, Pierce said. He also had an unspecified number of unused explosive devices described as Molotov cocktails.

Pierce said a 28-year-old man remained in in critical condition Tuesday evening at Wellstar Kennestone Hospital. Two men, ages 19 and 22, and a 52-year-old woman were in stable condition, and two other victims, a 42-year-old woman and a 38-year-old man, were treated and released.

Michael Nitzken, a doctor, told reporters that all the victims' wounds were consistent with shotgun blasts.

In a statement Tuesday evening, Kramer's father, Scott, said the family could "make no excuses for his actions and are shocked and devastated by them. There really are no adequate words at a time like this."

The statement began by expressing "our deepest sympathies and condolences to the victims" and offering prayer "for their complete and speedy recovery." Kramer said the family was also thinking of the FedEx workers "who were affected by Geddy's actions."

Liza Aiken, a fellow employee, told reporters that she was working nearby early Tuesday when she heard the "clink" sound of a knife hitting the floor, and looked up to see the suspect.

"He had an assault rifle. He had bullets strapped to his chest like Rambo," Aiken said. "I mean, he looked like he was heading into war. As soon as I saw him, I ran the other way. I ran and made sure that people upstairs were gone. He was in all black. I think he had a camo vest."

She described him as a "good worker" but added that he "seemed just like an immature boy."

Aiken said she had a disagreement with the suspect last week when he kept shining a laser scanner in her eyes. She said she reported him to a supervisor when he refused to stop.

Aiken said she doesn't know whether the altercation was a factor in the shooting or whether he was targeting her.

"He was quiet, friendly, we would joke around sometimes," she said. "I never thought he would do something like this.

More than 100 officers from Cobb County, the Atlanta Police Department, the Georgia Bureau of Investigation, the ATF and the U.S. Department of Homeland Security searched the facility for any "secondary devices that the shooter may have planted or was a part of," Pierce said.

FedEx employees arriving for the early-morning shift were turned away, WXIA-TV reported. Those already at the facility were held in a warehouse on the property while the facility was placed on lockdown. The facility is located at Cobb County Airport-McCollum Field.

FedEx spokesman Scott Fielder issued a statement from the company saying: "Our thoughts and prayers are with those affected, and with their families and friends. We are grateful for the assistance of law enforcement. 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."

Stanglin reported from McLean, Va.