At least 50 people were believed to be in a Chesapeake, Virginia, Walmart when a gunman opened fire Tuesday night, Chesapeake police said.

Authorities are still investigating a motive and are looking into the background of the suspect, 31-year-old Andre Bing, according to police. A search warrant has been executed at Bing’s house, police said.

Bing, who died at the store of an apparent self-inflicted gunshot wound, wasn’t wearing any type of armor or a ballistic vest, authorities said.

Police said they’re "still trying to account for anyone who may have been at the store and witnessed the incident, but fled prior to police arrival." Anyone with information is urged to contact the FBI at 1-800-CALLFBI.

The Walmart is expected to be closed for several days, police added.

Walmart employee Briana Tyler said she was with her co-workers in the break room around 10 p.m. when the gunfire broke out.

"My manager just opened the door and he just opened fire," Tyler told ABC News. "He wasn't aiming at anybody specifically. He just literally started shooting throughout the entire break room and I watched multiple people just drop down to the floor, whether they were trying to duck for cover or they were hit."

Tyler said the gunman looked "directly at" her and fired, but "luckily missed" her head by "an inch or two."

"He didn't say a word, he didn't say anything at all," she said. "He just came around the corner and started shooting. The first person that was in his eyesight, he shot him down.”

In another interview with ABC News later on Wednesday, she said the suspect, identified as 31-year-old Andre Bing, "was quiet and to himself" and "gave off ... the loner type."

"I've never once had, like, a joyous, fun conversation with him. It was always about work and that was it," she explained. "With everybody else, you know, a lot of people will, they laugh, they joke, I have other supervisors that I can, you know, talk to casually. But with him ... he wasn't like the fun, bubbly type of person."

Tyler, 28, is a mom to a 4-year-old son.

She said the shooting “taught me that life can literally be taken from you at the blink of an eye,” even when “doing something as innocently as trying to go to work.”

“So I would just say just reach out to the ones you love, keep an open relationship with them, do your best … because at the end of the day, you genuinely never know when you will look your child or your mother in their eyes again,” she said.

The suspect was identified by city officials as 31-year-old Andre Bing of Chesapeake. Walmart said he worked at the store as an overnight team lead and had been an employee since 2010.

Bing was armed with a handgun and had multiple magazines, officials said.

“We are focused on doing everything we can to support our associates and their families,” Walmart officials said in a statement. “We are thankful for the local first responders and will continue to work with local law enforcement as they continue their investigation.”

"We mourn the tragic and senseless loss of life in Chesapeake, Virginia," Department of Homeland Security Secretary Alejandro Mayorkas said in a statement.

Mayarkas said DHS "continues to devote every available resource to combat all forms of targeted violence. We provide information, funding, training, and other resources to communities throughout our country to enable them to prevent and respond to these horrific acts."

-ABC News’ Luke Barr

Walmart has announced plans to close the Chesapeake store for the "foreseeable future."

"All associates will continue being paid regardless of planned schedules," CEO John Furner wrote in an email to staff on Tuesday.

The company is supporting the victims' families with funeral, travel and other expenses, and the Walmart Foundation intends to contribute $1 million to the United Way of South Hampton Roads' Hope & Healing Fund, "which will support those impacted by the shooting and the broader Chesapeake community," Furner added.

-ABC News' Beatrice Peterson