ISLAMABAD - At least five people were killed and 15 others injured when a blast hit a passenger train in Pakistan's southwest province of Balochistan on Monday morning, local media Geo reported.

According to local media reports, the blast took place at about 9:30 am local time when a Jaffar Express train was on its way from Quetta, capital city of Balochistan, to Rawalpindi, sister city of the country's capital Islamabad.

The train was hit near Nasirabad, a district in eastern Balochistan, said local media, adding that four compartments of the train derailed following the blast.  

Earlier, a local TV channel reported that it was a rocket attack, but railway police later confirmed it was a blast caused by a bomb planted on the rail track, which was detonated by a remote-control device.

Police and rescue team rushed to the site after the explosion was reported and all the blast victims have been shifted to a civil hospital in Nasirabad.

An investigation into the incident has been kicked off.

So far, no group has claimed responsibility for the attack.