The incident happened in the Calabrian town of Marina di Gioisa Jonica Thursday, Italy's ANSA news agency reported.
Police said the victim apparently yelled at Boccucci Onofrio, 29, after being cut off while driving.
Onofrio then allegedly called on two friends, 15 and 17, to help him pull the other driver and his friend out of their car, police said.
The trio began to "ferociously" beat the couple with a rod and kick them, police said.
Two off-duty police officers came across the scene but were initially unable to help the couple because of a crowd that had formed.
The victims suffered contusions and broken bones and were taken to a hospital in the nearby town of Locri for treatment.
Onofrio was arrested at the scene.
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