Tulsa police have arrested a disgruntled Walmart worker in Oklahoma who they say threatened to shoot another store employee before responding officers found her sitting in a car outside with a loaded handgun, according to authorities.

The suspect, identified as Adrienne Edwards, allegedly made the threats after supervisors disciplined her for being "mouthy" during a shift last week, Tulsa police said in a statement.

Multiple witnesses told police they overheard the threats, which allegedly involved remarks about shooting a colleague.

Police said officers arrived to find Edwards in her car near the store's front door.

OHIO WALMART SHOOTING SUSPECT INJURES 4 BEFORE KILLING HIMSELF: POLICE

Police said she admitted to making the threats when they interviewed her around 7:40 a.m. in the parking lot.

Edward faces a charge of threatening a violent act.

WALMART EMPLOYEE IN CHESAPEAKE, VIRGINIA, KILLS 6 WITH PISTOL, POLICE SAY

The incident comes as the shopping chain and other retailers prepare for the busy holiday season – which is already known in the industry for increased stress, retail theft and even violence.

According to the National Institute for Occupational Safety and Health (NIOSH), retail workers are among the most exposed to workplace violence – especially convenience stores and gas stations where alcohol is sold. As a result, the Department of Labor advises taking all threats seriously.

The danger is largely driven by robbery crimes, however there have been deadly exceptions.

At another Walmart store in Ohio Monday, a man with a rifle barged in and shot four people before killing himself, according to police in Beavercreek, near Dayton. Three of the victims were hospitalized in stable condition, according to authorities. The fourth was critical.

And in Alaska, a man showed up at an Anchorage Walmart and shot a woman on her lunch break in a murder-suicide, according to the Anchorage Daily News. Police said it was a domestic violence incident.