Quetta: Three persons including a policeman were killed and more than 2 dozen others were injured a powerful blast here on Thursday. Police and rescue sources said the explosion occurred at Barroch Market area of Sariki Road near a vehicle of security agencies. As a result, a cop, and two pedestrians including a child died and 25 other peoples were injured who were rushed to the different hospitals of the city. The condition of at least six injured was termed critical. Police said six kilograms of explosive material was used in the blast. Quetta remained tense after the city braved four bomb blasts during just 14 hours.