At least one person was injured after a blast hit the customs intelligence office located at Airport Road of Quetta, the provincial capital of Balochistan, on April 1, reports Geo TV. A security guard posted at the office said that three unidentified armed persons had entered the office and held the staff hostage. He added that the persons had tied the hands of the staff and issued "grave threats to them". The guard said that the explosion took place as soon as the unidentified persons left the office. So far, no group has claimed responsibility for the attack.