The Pakistan Stock Exchange building in the city of Karachi was stormed by armed men Monday in an attack that left three law enforcement officers and all four gunmen dead. Reuters reports separatist insurgents from Balochistan—one of the four provinces of Pakistan—have claimed responsibility for the attack. The police chief in Pakistan’s largest city are reported to have said the gunmen pulled up outside the building in a silver Corolla car before launching their attack with grenades and firearms. They reportedly threw a grenade at security men just outside the compound then opened fire on a security post. Two guards and a policeman were killed and seven people were wounded, according to Deputy Inspector General of Police Sharjil Kharal. The four gunmen were killed by security services. The Pakistan Stock Exchange carried on trading during the attack.