At least 13 people were burnt to death and 17 others injured when a passenger van collided with a bus and caught fire in Punjab's Sheikhupura district on Monday, rescue sources and officials said.

The blaze destroyed both the vehicles and left passengers' bodies charred beyond recognition.

The accident took place on Narowal Road in Narang Mandi when the speeding bus travelling from Narowal to Lahore collided with the van coming from Lahore in the opposite direction, a Rescue 1122 statement said, adding that the incident apparently occurred due to fog in the area.

After the collision, the LPG cylinder fitted in the van exploded, with the blaze engulfing the entire vehicle within moments and leaving 13 of its passengers dead. Passengers on board the bus were able to disembark before it caught fire.

Rescue services reached the site of the accident, doused the fire and pulled out the bodies from the wreckage.

The 17 injured were shifted to Narang Mandi Rural Health Centre (RHC) after being administered first aid and were subsequently taken to Lahore's Mayo Hospital. The bodies of the deceased, who could not be identified as yet, were shifted to Muridke Tehsil Headquarters (THQ) Hospital.

Seven of the deceased belonged to the same family. They were travelling home in the van after attending a wedding in Lahore, according to Rescue 1122.

Speaking to reporters, Sheikhupura Deputy Commissioner Muhammad Asghar Joiya confirmed the death toll and injuries, saying the accident that took place near Meeran Shah Darbar was apparently the result of over-speeding. He said it was always advised to drive slowly in foggy conditions.

Thousands of people lose their lives in traffic accidents across the country every year that are caused due to poor roads, badly maintained vehicles and reckless driving. Crashes killing dozens of people are not uncommon.

Earlier this month, 12 people were killed and 30 others injured in a head-on collision between a bus and a truck in Pindi Bhattian.

In September, 13 people were killed and several others injured when a passenger van overturned and caught fire on the Karachi-Hyderabad Motorway (M-9) in the jurisdiction of Nooriabad police station.