QUETTA - Two young sisters were killed and their brother wounded in a hand grenade attack in Quetta here on Thursday night while five others were also wounded in separate incidents of rocket attack. According to police, unidentified motorcyclistss hurled a hand grenade at the house owned by a government servant Gulzar Ahmed on Sariab Road nearby Mussa colony. Grenade landed inside the house and went off with a huge bang killing Rabia, 9, on the spot and seriously wounding her sister Iqra, 7 and brother Jalal, 8. The injured and deceased were rushed to the Civil Hospital Quetta where Iqra also succumbed to her injuries. Soon after the incident, police and personnel of Frontier Corps reached the site and cordoned off the area. The attackers managed to escape from the site after throwing the grenade. 'Children were playing at courtyard of the house when the grenade land with huge blast, said a police official. The blast also scattered windowpanes of the house and other nearby buildings. Hospital sources said that the condition of injured Jalal is serious. Police handed over the bodies to heirs after completing legal formalities and started further investigations. Meanwhile, Chief Minister Balochistan Nawab Muhammad Aslam Khan Raisani has expressed shock and grief over the killing of two young sisters and injury to their younger brother. He directed authorities concerned for immediate arrest of culprits involved in this heinous crime. On the other hand, unknown people fired three rockets in provincial capital which landed in different parts and wounded five people. The first rocket landed in Shahbaz Town, hitting the residence of Muhammad Tayab. Rocket exploded and wounded five people. Similarly, second rocket landed in Zarghoon Road on the rooftop of a house. However, no loss of life occurred. Police has registered four different cases of all incidents and started further investigations.