PARIS (AP) — They only went out to play a calm game of petanque and enjoy some late summer warmth by a Parisian canal. By the end of the evening, the three friends had neutralized a knife-wielding attacker who had stabbed seven people, with an unlikely weapon: the game’s clanking — and hefty — metal balls.

Lobbing them in their dozens at the attacker and whacking him on the head with a wooden plank, they managed to bring the horror that befell the 19th district on Sunday night to an end. The attacker is now in custody and police are trying to piece together what happened and what the attacker’s motivations for his bloody rampage were. Without the bravery of the three friends, and the normally-slow-moving steel globes, it could have been a lot worse. The area, after all, was full of revelers from a popular cinema complex, tourists and families. Two British tourists were among those injured. Luckily for everyone there, petanque player Boudjema Hamani and his two friends were on hand and ready to wield their own weapons of choice.

Petanque, a typically Gallic pastime played by some 20 million French in which a ball is slowly rolled along the gravelly ground, is ubiquitous in Parisian courtyards in summer months. It’s popular with the elderly, and does not have a reputation associated with danger, action or speed.

In a surprise response at 11 p.m., the friends — none of whom can be considered elderly — chased the attacker down the street and showered him with their normally-peaceful steel spheres that can weigh a kilogram.