Clayton Parks served as HR manager for Aurora, Illinois-based Henry Pratt Co. and was among the employees who sat in on a termination meeting when a worker who was fired took out a gun and shot Parks, CNN reports. That employee, Gary Martin, also was accused of shooting Trevor Wehner, an HR intern, at his first day working at the firm and three other employees.

Parks, Wehner and the three other employees were all killed in the shooting. Five police officers were injured and Martin was killed in the ensuring gun fight.

"The point of termination is perhaps the greatest opportunity for deadly workplace violence," Kathleen Bonczyk, founder and executive director of Florida-based non-profit Workplace Violence Prevention Institute, told CNN.

Workplace violence impacts nearly two million Americans every year, according to the Department of Labor's Occupational Safety and Health Administration (OSHA) website. Of the 4,679 fatal workplace injuries in the U.S. in 2014, 403 were homicides, Bureau of Labor Statistics Census of Fatal Occupational Injuries data finds.

"However it manifest itself, workplace violence is a major concern for employers and employees nationwide," OSHA noted.

A firearm was involved in just over three-quarters of workplace killings in 2017, CNN notes, citing the Bureau of Labor Statistics. And of the 458 workplace homicides in the U.S. that year, 351 were from shootings, CNN reports, citing the most recent government data. In 2016, there were 500 workplace homicides, with 394 of that total involving gun fire.

"It's almost like a divorce from a family," Bonczyk said. "Americans today tend to spend more time at work than they do even at home. They tend to have more lunches, dinners, meals, time spent with their coworkers. You're severing perhaps the most stable relationship that the employee may have."

While it may be tempting for employees who've experienced violence at their workplace to want to be armed, there are many things that can go wrong, says Mark Lies, a partner at Seyfarth Shaw in Chicago. Lies made his comments to the Society For Human Resource Management last year.

One such scenario could involve an employer who allows guns in the workplace and a manager ends up firing the weapon. "The issue will then become whether the manager exceeded the scope of reasonable force and acted negligently or recklessly," Lies said.

That manager could expose themselves to a host of civil damages including personal injury, wrongful death and intentional infliction of emotional distress. There also could be punitive damages if a shooting is found to be reckless.

Instead of permitting managers to be armed at work, employers could look to other measures, including inviting a trained safety consultant to do an assessment, says Rodney Moore, an attorney at Atlanta-based Ogletree Deakins. That consultant can help employers deal with vulnerable access points at the worksite and any issues that might foster violence.

Employees also can be trained to spot potential red flags and how to react. "The basics, like having awareness and a solid safety plan, really can help in an emergency situation," Moore said.

While it can be challenging, employers need to recognize trigger points and act fast to deal with them. So writes Karen Michael, an attorney with Richmond, Virginia-based KarenMichael law firm, in the Richmond Times-Dispatch.

"One strategy to avoid a trigger is to make sure that employees enjoy transparency and respect during any disciplinary process," she noted. "Even if someone has embezzled funds or engaged in severe misconduct, employers should respectfully explain the basis for the decision and then professionally address the process of exiting the employee."