AUGUSTA, Maine (AP) — A violent struggle inside a Maine Wal-Mart started with a comment over an untied shoelace and ended with gunfire, according to one of the men involved, but police say a death outside the store was unrelated.

Investigators say 31-year-old Robert Potter pulled a gun on another customer during an argument Monday night at the Wal-Mart in Augusta. They say the gun went off as the other man tried to disarm him. No one was hit.

Police say a woman apparently witnessed the fight and ran to the parking lot, where she suffered a medical emergency and died.

The other man involved in the fight, Kevin Roberge, tells the Kennebec Journal the dispute started when he told Potter one of his boots was untied.

Potter was arrested and hospitalized for unspecified treatment.