Eight people were killed and 35 others wounded in a an attack on the regional office of Pakistan's ISI intelligence agency in the southern city of Sukkur, media outlets said Thursday.

At least four heavily armed attackers fired shots and launched grenades at the complex Wednesday night before detonating an explosives-laden car, the Express Tribune said, citing unnamed officials.

Three ISI personnel and a civilian were killed along with all four assailants, police told the newspaper.

The ISI's deputy regional director, identified only as Maj. Zeehan, was among the dead, several media outlets said.

Prime Minister Nawaz Sharif energetically condemned the assault.

Though it plays an important role in Pakistan's struggle with armed insurgents, Wednesday night's attack was the most significant mounted against the ISI since 2009, when 34 of its officers died in assaults on the spy agency's offices in Lahore and Peshawar. EFE