At least 152 people died on Wednesday morning as a private commercial airliner, Airblue, crashed into Islamabad's Margalla mountains after being denied landing on its first approach to Islamabad Airport.
The crash of the Airblue aircraft took place as the A321 aircraft crashed into the mountains that skirt Pakistan's federal capital with civil aviation authorities saying that this could possibly signal pilot error.
Officials said that the plane did not follow the prescribed flight path under which it would have to turn left after gaining altitude from the Islamabad airport. Instead, it went straight and hit the mountain.
Pakistan has declared a day of mourning.
The flight had originated from Manchester and had stopped at Turkey and Karachi on its way to its final destination of Islamabad. Prime Minister Yousuf Raza Gilani has ordered an investigation.
Initial reports suggest that the plane was denied landing at the Benazir Bhutto airport in Islamabad due to foggy conditions and flight traffic. It was asked to make another approach which it was doing at the time of the crash.
Two Americans were also among the victims, a US embassy spokesman told Reuters.