KARACHI   -   At least 13 people died and several others wounded critically when a passenger van overturned and caught fire on the Karachi-Hyderabad Motorway (M-9) in the limits of Nooriabad police station, police said late Saturday.  The van carrying at least 20 people was moving in high-speed when the accident took place near the Lucky Cement factory located on the route.  Police officer Dr Aftab Pathan told reporters that five people were shifted to a nearby hospital with multiple injuries. He said six of the bodies were recovered while the survivors included the van driver and a child.  The bodies were yet to be identified. An official said the van was on its way to Karachi from Hyderabad when the accident took place. An eyewitness told the police that the van overturned and caught fire after bouncing off the road. He said the passengers' bodies were completely charred. Edhi ambulances and firefighters rushed to the spot and launched the operation soon after the incident. The flow of vehicular traffic was suspended as police closed the Hyderabad-Karachi section of M-9.