ISLAMABAD, July 30 (Xinhua) -- A blast triggered by an improvised explosive device hit a police vehicle in Pakistan's southwest Quetta city on Tuesday evening, leaving at least four people dead and 28 others injured, police and hospital official said.

In this picture taken on July 23, 2019, Pakistani security officials examine the site of an improvised explosive device (IED) blast in Quetta. (File Photo: VCG)

Medical Superintendent of Civil Hospital Quetta Saleem Abro told the media that four bodies, including two policemen, and 28 wounded were brought to the hospital. The death toll might further rise as six of the injured were in critical condition, said the official.

Deputy Inspector-General of Quetta Police Abdul Razzaq Cheema said the police vehicle came under attack near the City Police Station located in the busy Liaqat Bazaar market of Quetta, the provincial capital of the southwest Balochistan province.

Rescue teams, police and security forces rushed to the site and shifted the bodies and injured to the hospital. Majority of the wounded are civilians who were shopping in the market.

Police said the bomb was planted in a motorbike parked near the vehicle and it was detonated with a remote-controlled device.

No group has claimed the attack yet.

Police and security forces have cordoned off the area and launched a search operation to arrest the perpetrators.