Peshawar, Dec 5 (Inditop.com) At least four people were killed and over 15 injured in an explosion near an office plaza in this North West Frontier Province (NWFP) capital but the incident was not a terrorist attack, a police officer said.

Peshawar police chief Liaquat Ali said that the blast, which occurred in in a chemical shop in the University Road area, was not an act of terrorism.

Confirming this, the additional inspector general of the Bomb Disposal Squad, Shafqat Malik, said the blast was the result of an accident, Online news agency reported.

Eyewitness said the first blast occurred at 10.50 a.m. and was followed by a series of smaller blasts.

A fire broke out after the blasts and a number of people were trapped in the three-storey office plaza.

More than 20 shops and offices were destroyed in the blasts.

Some CNG stations were also located in the area and heavy smoke was billowing out of the blast site as fire tenders reached the spot. A large number of Afghan refugees live in the area.

Rescue activities began immediately after the blast, with the local people lending a hand. The injured have been shifted to the Lady Reading and Khyber Teaching Hospital.

Police cordoned off the area after the blasts and the University Road and the Khyber Road were closed to the public.

Interior Minister Rehman Malik, while condemning the incident, has sought a report from the provincial police chief.

However, NWFP Information Minister Iftikhar Hussain said the blast was caused by a bomb planted in a car parked near the office plaza, adding that terrorists wanted to pressurise the government by targeting innocent people.

Talking to a private TV channel, he said that foreign countries are involved in terrorism incidents in the province.

Pakistani President Asif Ali Zardari and Prime Minister Yousuf Raza Gilani have strongly condemned the blast and directed the authorities to provide proper medical facilities to the injured.