An 86-year-old man in Puerto Rico has been charged with murder after police accused him of killing a 60-year-old man during a fight.

Authorities say Angel Quinones began arguing with David Lugo late Thursday and that both began punching each other. Police accused Quinones of then taking a knife and stabbing Lugo in the chest.

Police said Friday they're investigating what led to the fight and whether the men knew each other.

The killing occurred in the northwest town of Camuy.