A powerful blast on Saturday rocked a restaurant in the heart of Islamabad, killing one foreign national and injuring 15 persons including Americans, Chinese and Japanese.

The explosion took place on a lawn outside the Luna Caprise restaurant at about 8.40 pm and the sound could be heard from several kilometres away.

One foreign woman has been confirmed dead in the blast.

Among those injured were three US citizens, two Japanese journalists, two Pakistanis and one Chinese, Islamabad Police Chief Nadeem Baloch said.

Baloch, however, ruled out a suicide attack.

The place is frequented by foreigners and diplomats, and several US embassy cars were parked outside the eatery at the time of the blast, which caused a huge crater at the scene.

The incident created panic in the city and police immediately cordoned off the area, located in the busy Super Market, as ambulances rushed to the site.