*UPDATE* 11/7 2:45 p.m. – Augusta police confirmed in a release Tuesday that a confrontation inside Walmart led to a shot being fired.

Police said Robert Potter, 31, of Augusta, was a patron who became engaged in an argument with another customer. They said Potter pointed a firearm at the other customer, who attempted to defend himself by disarming Potter. This led to one round being discharged from the firearm.

Potter was charged with Class C criminal threatening with a dangerous weapon.

Robert Potter
Robert Potter

Police also clarified the situation surrounding the death of a woman outside.

They said the woman was entering the store as the confrontation was unfolding when she ran back to her vehicle and suffered a medical event.

Police said there is no evidence to suggest she was associated with the situation inside Walmart or she was anything other than a witness.

AUGUSTA, Maine (NEWS CENTER) — A man is in custody after a shot was fired inside Walmart in Augusta.

Police said the suspect entered the store around 8 p.m. Monday with a firearm, and a confrontation ensued with another person inside — referred to by police as a "good Samaritan" — who was trying to disarm the man with the firearm. They said one shot was fired within the building.

A woman passed away outside the store, separate from the altercation inside, according to Augusta Police Deputy Chief Jared Mills.

The woman's official cause of death was not immediately known, but Mills said it wasn't due to "a gunshot wound or anything that was apparent" and that police would be working with the medical examiner's office to determine exactly what happened.

No one was hurt inside and the suspect was brought into custody quickly. Mills said an Augusta police officer was just around the corner and responded within minutes of initial reports.

Police said they do not think the suspect entered the store with the intent to harm. But he said given the situation of someone entering a packed store with a firearm and getting into an altercation, "we still don't know" and are "keeping an open mind."

Police also said it does not appear the suspect and good Samaritan knew each other.

WATCH: Full press conference with Augusta PD's deputy chief

Surveillance captured the altercation on camera and police said in addition to reviewing that they have a number of witnesses providing accounts.

Asked to comment on the relation between the incident and current events, Mills said it's unfortunate we're having to deal more and more of these types of incidents around the country.

"Ten years ago this wasn't something we were dealing with on a day-to-day basis," Mills said. "Certainly not here in Augusta, Maine — it's a very safe community and we don't have a lot of this happening."

Following standard protocol, Mills said state police were called out of precaution due to the proximity between the death and shooting, pending any possible connection.

Mills was confident law enforcement would determine a motive and said police were already working with the Kennebec County District Attorney's office on possible charges against the suspect.