Islamabad, April 28 (IANS): At least eight people were killed and 17 others injured in a blast Sunday outside the office of an independent election candidate in Pakistan's northwest tribal region, a media report said.

The blast took place around 9.50 a.m. outside the poll office of Syed Noor Akbar in Kacha Paka area of Kohat town in Khyber Pakhtunkhwa province, some 160 km from Islamabad, Xinhua reported citing Urdu TV channel Ary.

Akbar is contesting for the National Assembly seat from the nearby tribal area of Orakzai. He was unhurt in the blast.

Kohat district police officer Dilawar Bangash, however, said only three people were killed.

The blast also damaged several vehicles and buildings in the area.

No group claimed responsibility for the attack.

In recent days, blasts mainly targeting election rallies have been reported across the country. On Saturday night, two blasts targeting an election office and public gathering of two parties took place in the port city of Karachi, killing at least four people and wounding many others.

The Pakistani Taliban have warned people to avoid political rallies ahead of the May 11 general elections.