The cause of the Airblue crash was not immediately clear, said Pervez George, a civil aviation official. He said the plane was flying from Karachi to Islamabad and was trying to land during difficult weather. Airblue is private service based in Karachi, Pakistan's largest city.
"The plane was about to land at the Islamabad airport when it lost contact with the control tower, and later we learned that the plane had crashed," George said.
Guards with the forestry service said they had found some wreckage and seen at least five dead bodies, said Imtiaz Inayat Ali, an official with Islamabad's Capital Development Authority. Amir Ahmed, the city's deputy commissioner, told the ARY news channel that rescuers had found at least three people who were alive but wounded.
"This is a miracle as we had been briefed that there might not be any survivors," Ahmed said.
Pakistani news channels showed what appeared to be wreckage of the plane as a helicopter hovered above the heavily forested hills to assess the situation. Fire was visible and smoke was blowing up from the scene. The army said it was sending special troops to the area to help out along with helicopters.
Mohammed Usman, an official at the Benazir Bhutto International Airport said dozens of relatives of passengers gathered there were crying and desperate to get information about their loved ones.
Saqlain Altaf told Pakistan's ARY news channel that he was on a family outing in the hills when he saw the plane, looking unsteady in the air.
"The plane had lost balance, and then we saw it going down," he said, adding he heard the crash.
Airblue could not immediately be reached for comment.
Officials at first thought it was a small plane, but later revised that. George said 146 passengers were on the flight along with six crew members.
The only previous recorded accident for Airblue, a carrier founded in 2003, was a tailstrike in May 2008 at Quetta airport by one of the airline's Airbus 321 jets. There were no casualties and damage was minimal, according to the U.S.-based Aviation Safety Network.
Airblue flies within Pakistan as well as internationally to the United Arab Emirates, Oman and the United Kingdom.
Other Pakistani airlines have come under international scrutiny due to safety concerns.
In 2007, the European Union temporarily banned flights in its airspace of most of the aircraft operated by Pakistan's national carrier, Pakistan International Airlines, because of concerns over the age of the aircraft and poor maintenance. The bloc lifted the ban later that year after the airline took action to comply with safety standards.
The last major plane crash in Pakistan was in July 2006 when a Fokker F-27 twin-engine aircraft operated by Pakistan International Airlines slammed into a wheat field on the outskirts of the central Pakistani city of Multan, killing all 45 people on board.
In August 1989, another PIA Fokker, with 54 people onboard, went down in northern Pakistan on a domestic flight. The plane's wreckage was never found.
In September 1992, a PIA Airbus A300 crashed into a mountain in Nepal, killing all 167 people on board. Investigators found the plane was flying 1,500 feet lower than it reported as it approached the Katmandu airport.
Source: The Huffingtonpost