At least six people were killed and over 35 others were injured when some unknown militants attacked Pakistan's Inter services Intelligence (ISI) in the country's southern district of Sukkur on Wednesday evening, local media and police said.
Masood Bangash, the deputy superintendent of police said that a suicide bomber rammed his explosive laden vehicle into the ISI building complex, constituting of a number of government offices in Sukkur, a main district in the country's southern Sindh province.
The blast left a few feet long and deep crater outside the ISI complex.
Followed by the vehicle blast, four suicide bombers sneaked into the building, three of them blew themselves up during the exchange of firing with the police while the fourth one was arrested by law enforcement agencies.
Eyewitnesses said that the militants first hurled hand grenades at the ISI complex, causing a few blasts, later some of them sprayed bullets at the building and one attacker hit his vehicle into the Intelligence Agency's building.
Following the blast, police conducted a door-to-door search operation in the nearby area as some police officials expressed fear that some militants might be hiding in the area where other government offices including Commissioner House and Rangers' headquarters are located.
The ISI building was partially collapsed in the blast while roofs of several nearby building also razed to ground due to the high intensity of the blast. Several government and private vehicles were also destroyed.
The injured people including ISI employees have been shifted to a nearby hospital where several of them were in a critical condition.
The dead people included an ISI employee, a private gardener and four militants.
No group claimed responsibility for the attack yet.
Both President Asif Ali Zardari and Prime Minister Nawaz Sharif condemned the blast and directed hospital authorities to provide best medical treatment to the injured people.
