The pair were patrolling a road in Taunton when they noticed a man using his mobile behind the wheel.
Footage shows the officers trotting into action, turning their horses around before chasing down the vehicle.
One of the mounted officers is then heard reprimanding the driver for using his mobile.
“Drivers face six points and £200 fine if caught using a phone,” Avon and Somerset Police tweeted, sharing the clip.
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