Emergency teams braving heavy rains and slush were continuing efforts to recover bodies and 'black box' and flight data recorder of the ill-fated Pakistani passenger plane to know why the aircraft went off course and crashed while coming into land.
The rescuers are yet to recover even a single body intact with the wreckage of the aircraft strewn over two sides of a hill and a deep ravine located near the Daman-e-Koh viewpoint.
The efforts to locate the bodies continued as Pakistan on Thursday observed a day of national mourning for the 152 people killed in the worst aviation accident in the country's history.
The Airbus A321 operated by private airliner Airblue crashed into the Margalla Hills overlooking Islamabad amid heavy monsoon rains and bad weather on Wednesday. The crash occurred shortly before the flight from the southern city of Karachi was to land at the airport in the capital.
There was no official word on the cause of the crash.
Officials said they were yet to find the aircraft's "black box", which they expected would help in determining the reason for the crash.
Pakistan Interior Minister Rehman Malik had initially said there were 155 passengers and crew members on board. Lists issued later by Airblue and authorities showed there were 146 passengers and six crew on the aircraft, which was seen flying at an unusually low level before it crashed into the Margalla Hills, which is a no fly zone.
Prime Minister Yousuf Raza Gilani declared on Thursday a day of national mourning and ordered flags to be flown at half-mast across the country.
Police officials and rescuers said they had not found even a single intact body at the crash site. The remains, tied in bags by rescuers, were airlifted from the crash site by helicopters and transported to the Pakistan Institute of Medical Sciences. Officials said they had received the remains of over 130 passengers till late on Wednesday night.
Officials were quoted by TV news channels on Thursday morning as saying that the remains of 68 victims had been identified while the remains of 58 had been handed over to their relatives.
They said most of the remains were mutilated and charred, making the process of identification very difficult. Authorities set up a special facility at a community centre to conduct DNA tests on relatives of victims to identify the remaining bodies.
The search operation at the crash site, which was suspended last night, resumed this morning amidst heavy rains. Rescuers said they were focussing on gathering up human remains and belongings of passengers and finding the flight data recorder or "black box".
Rescuers used ropes to make their way up the steep hillsides, made slippery by the rain. Army soldiers, paramilitary personnel, forest guards and members of a state-run rescue service are involved in the search operation.
Details released by authorities showed two American nationals, seven children and 29 women were among the victims.
Interior Minister Malik said an inquiry by the Civil Aviation Authority would determine the cause of the crash. According to first-hand information, poor visibility might have been one of the reasons for the accident, he said.
Experts questioned why pilot Pervez Iqbal Chaudhry, a professional with 35 years of experience, had veered away from the airport and headed towards the Margalla Hills and a no-fly zone over some of Islamabad's most important official buildings, including the presidency and parliament.
They pointed out that the aircraft's co-pilot, a former fighter pilot of the Pakistan Air Force, was making only his second flight after joining Airblue.
The experts also said many flights from Karachi to Islamabad had been cancelled in recent days because of bad weather and questioned why the Airblue plane was allowed to fly.
Airblue spokesman Raheel Ahmed told reporters that the plane had no history of technical problems. It was built ten years ago and leased by Airblue in 2006.
Image: A family member of an Airblue plane crash victim weeps after recovering the body at a hospital in Islamabad on Thursday
Photograph: Adrees Latif / Reuters