Police officials told Dawn News that unidentified individuals had planted an improvised explosive device (IED) on the track in the Nuttal area of Nasirabad.
Police and Frontier Corps personnel rushed to the spot after receiving information about the device.
The area was cordoned off immediately.
The bomb disposal squad also reached the location and safely defused the IED, Nasirabad SSP Ghulam Sarwar Bhaou told Dawn News.
He added that the attackers wanted to target the Peshawar-bound Jaffar Express, but timely action saved the train from a potential blast.