At least three policemen were injured on Saturday when a gang attacked a police party with pepper spray and escaped with an undertrial prisoner who was brought to a hospital in Haryana's Panchkula town.The incident took place outside the Panchkula General Hospital, which is located just a few metres from the Haryana Police state headquarters.The three injured policemen were admitted to the same hospital.The attackers confronted the police party outside the hospital and used pepper spray, blinding them. The attackers also fired shots in the air before escaping.