Death toll of Wednesday morning 's hand grenade blasts and firing in Pakistan's southern port city of Karachi has risen to 15, local media and police said. Faisal Bashir, superintendent police, said that the violent incident that happened on Wednesday morning was an outcome of a clash between two rival groups that killed 15 people including the gang leader's brother and four women and injured over 30 people including school children. The violence broke out when members of two rival gangs opened fire and hurled hand grenades at each other after exchanging harsh words in Jhat Pat market of Karachi city. Police said that one of the gangs kidnapped member of the other earlier on Tuesday night which led to the fierce clash. Eyewitnesses said that they heard six to seven small explosions in Lyari area of the city where the market is located. The injured people have been shifted to Civil Hospital. The women and kids were shopping in the area and some kids were going to school when the attack happened, police said. Police cordoned off the area for investigations. Lyari is a restive area in Karachi, the capital city of the southern Sindh province, which is considered to be center of gang war and a hub of extortion mafia. Heavy contingent of police and paramilitary troops were deployed across the whole Lyari area following the incident to control any untoward situation Prime Minister Nawaz Sharif called Interior Minister Chaudhry Nisar Ali Khan and discussed about law and order situation of the city with him.