Without warning, the axe-wielding man went on a rampage inside the Ica Kvantum grocery store located in the Odensala neighbourhood.

“An older man received at least one blow from an axe, a blow which hit him in the head. The man has been taken by ambulance to Östersund hospital. We don’t yet know how serious the man’s injuries are,” said Jämtland police spokesperson Ann-Christin Johnsen to the TT news agency.

The attacker was quickly overpowered by onlookers, staff, and guards who had been summoned to the scene.

During the scuffle, at least one other person received minor injuries.

The man was then arrested by police.

The Östersunds-Posten newspaper reports that police believe the man suffers from a mental illness and that he was attempting to rob the store at the time of the attack.

Store workers who witnessed the incident were in a state of shock and are expected to receive help during the day to recover from the dramatic assault.

The store’s management has called in extra staff in order to keep the store open for the remainder of the day.