Three small explosions were heard in different areas of Karachi . First was flung on a police station in Gulshan-i- Iqbal Karachi . A constable on duty had minor injuries. A policeman spokes an unidentified assaulter hurled the grenade and fled away. Road was temporarily blocked. 2ND near a bus station in Karimabad. It damaged the boundary wall of APWA College for girls. The third was about 20 feet away from a school in north Nazimabad. CM Qaim Ali Shah took notice of the incident.