Apparently the A320 stopped takeoff roll from Karachi Airport Runway 25L at low speed of 15 knots at 4:29 PM. PIA flight PK308 to Islamabad was scheduled to depart from Karachi at 4:00 PM.

Source: flightradar24.com
PIA Engineering team at Karachi Airport is working to remove technical problem in the aircraft.
Karachi Airport runways:
Runway 07L/25R
Runway 07R/25L

Abbas