Updated

The union representing security guards at the Holocaust museum in Washington had been fighting for bullet-proof vests, but the company hadn't issued them at the time of Wednesday's deadly shooting.

One guard was killed when police say, a lone white supremacist gunman burst into the U.S. Holocaust Memorial Museum and opened fire.

Stephen T. Johns, 39, wasn't wearing a protective vest when James W. von Brunn allegedly shot him, according to The Washington Post.

Click here for photos.

The Security, Police and Fire Professionals of America said the union lobbied security contractor Wackenhut Services Inc. for protective vests during contract negotiations two years ago, the Post reported.

But the company-bought vests weren't provided, even though Wackenhut seemed in favor of the proposal, the union's Washington district director Assane Faye told the Post.

"I hammered this in our negotiations two years ago because of how sensitive that museum is," Faye said. "Our guards needed more protection."

One of the museum's guards had been "verbally assaulted by one guy walking by, saying anti-Semitic remarks," Faye told the paper. "For that reason, I made that the center of the negotiation."

Wackenhut spokeswoman Susan Pitcher declined to comment on the matter.

Johns worked for Wackenhut, which has contracted security services at the museum since 2002, according to a company statement. Johns had been posted at the museum since joining the firm in 2003. The museum has about 70 officers and supervisors on the force.

Guards are armed with .38-caliber revolvers and dress in police-type uniforms, the company said. It said preliminary details indicate the officers responded appropriately when facing the gunman, who opened fire with a rifle.

Click here for more on Von Brunn's background.

Click here for more on this story from The Washington Post.

The Associated Press contributed to this report.