ISLAMABAD, July 25 (Xinhua) -- At least five people were injured when a blast went off near a police vehicle in Pakistan's southwest Quetta city on Wednesday, local Urdu TV channels reported.

According to the reports, the explosion occurred in the eastern bypass area of Quetta, the provincial capital of the country's southwestern Balochistan province.

The attack happened when a police vehicle was passing by a polling station in the area, the reports said.

Nature of the explosion has not been officially confirmed yet.

Security forces and rescue teams rushed to the site and shifted the injured to nearby hospital in the city.

Security forces condoned off the area and kicked off a search operation. No group or individual has claimed the attack yet.