Distraught relatives gathered Friday for the first funerals of some of the 74 people killed when fire ripped through a crowded train near Rahim Yar Khan, with many of the victims residents of a single town. Sobbing family members crowded a government building in Mirpurkhas overnight as the first bodies covered in white cloth began arriving by ambulance from the scene of the disaster.

After morning prayers, with women watching from nearby rooftops, more than a hundred men attended the first funeral - of a car mechanic named Mohammad Saleem, who was in his late 40s. It was held at the Bismillah Mosque, from which at least 42 pilgrims had left to board the train one day earlier, bound for a religious festival near Lahore.

Officials say as some of the train's passengers cooked breakfast around dawn Thursday, two of their gas cylinders exploded, sending flames racing through three carriages as the train passed near Rahim Yar Khan, in Punjab province. At least 74 people died, some after jumping through windows on the still-moving train to escape the blaze.

Rescue officials found bodies and some injured passengers along a two-kilometre stretch of track, Dawn newspaper reported. The train was a daily express service that runs between Karachi and Rawalpindi, adjacent to Islamabad. Trains on that route can reportedly hit speeds of up to 110 kilometres (68 miles) per hour. Local media said that the speed may have helped fan the flames. Journalists were allowed inside the interior of the carriages early Friday. The fire appeared to have burned them entirely, with virtually no space visible that was not blackened and charred.

One of them - Wagon No.12 - was carrying mainly people from Mirpurkhas, the town's deputy commissioner, Attaullah Shah, told AFP. "There was never such a tragic incident to happen to Mirpurkhas," he said. Eight of the bodies had been confirmed as being residents of the town so far, he said. Twenty-four Mirpurkhas residents were among the injured.

But at least another 40 are still missing, he said. Officials in Rahim Yar Khan have said many of the bodies are charred beyond recognition and will have to be identified through DNA testing - a process that could take up to one month. Shah said the government was arranging to send families of the missing from Mirpurkhas to the hospital in Rahim Yar Khan where the bodies have been taken.