ISLAMABAD (Reuters) - A Pakistani passenger plane crashed in heavy rain near Islamabad Wednesday, killing all 152 people on board, officials said, in the worst aviation accident in Pakistan.

The Airbus 321, belonging to a private airline crashed into a heavily wooded and hard-to-access hillside while flying from the southern port city of Karachi.

Federal Information Minister Qamar Zaman Kaira said 115 bodies had been recovered so far but bad weather and difficult terrain above the city had hampered search efforts.

“Unfortunately, no one survived ... Many bodies are not in good shape,” Kaira told a news conference.

Twelve bodies had been identified so far, but “the crash was very terrible. There was fire. It’s difficult to recognize the bodies.”

Passengers’ remains were badly damaged in the crash and DNA tests would be used to identify the victims, he said.

Two Americans were among the victims, a U.S. embassy spokesman told Reuters. He had no further details.

While thick fog and rainy weather are considered the most likely reasons for the crash, Kaira declined to rule out sabotage and said all possibilities would be investigated.

Kaira said the plane’s “black box” data recorder had yet to be recovered.

The plane lost contact with the control room of the Islamabad International Airport at 0443 GMT. It was carrying 146 passengers and six crew members.

“The pilot was given directions to land either on runway I or II,” Interior Minister Rehman Malik told reporters. “The plane was at 2,600 feet before landing but suddenly it went to 3,000, which was unexplained.”

“If the visibility to the runway was so poor then it should have been diverted.”

Defense Minister Ahmed Mukhatar said the control tower at the airport had been sealed and a team would examine the data recorder and radio traffic between the plane and the tower.

“If you look at the position of the wreckage it’s clear that the plane went beyond safety margins. It should have maneuvered within five miles of the runway but it did not happen,” said Ejaz Haroon, managing director of state-run airline PIA.

The crash site is on the Margalla Hills facing Islamabad, about 300 metres (yards) up the side of the hills. Smoke could be seen from some districts of the city after the crash.

While Wednesday’s crash is the worst aviation accident on Pakistani soil, PIA has had two worse disasters. In 1979 and 1992, PIA jets crashed in Jeddah, Saudi Arabia and Kathmandu, killing 156 and 167 people, respectively.

Within Pakistan, the last major aviation accident was in 2006 when a PIA plane crashed near the central city of Multan killing 45 people.

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NEW PLANE

The military sent three helicopters to the site and troops also were deployed. Prime Minister Yusuf Raza Gilani surveyed rescue operations from the air and the government declared Thursday a day of mourning for the victims.

AirBlue began operations in 2004 with a fleet of Airbus A320 and A321 aircraft, according to its website www.airblue.com. It flies primarily domestic routes as well as to the United Arab Emirates, Oman and Manchester in Britain.

Spokesman Raheel Ahmed said this was the first crash for the airline and that an investigation was being launched.

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“It’s too early to speculate,” he said about the cause of the crash. “The civil aviation authorities will also be involved.”

Airbus confirmed one of its planes was involved in the AirBlue crash.

“We regret to confirm there has been an accident with an Airbus aircraft and we will provide more information when we have more confirmed data available,” said Airbus spokesman Stefan Schaffrath.

At Islamabad’s international airport in the moments after the crash, passengers in the departure lounge scanned the television screens for news.

“I’m not surprised something like this has happened,” said Ahmed Fairuz, a passenger awaiting departure. “The weather is just too bad for flying.”

Aviation industry sources in Europe said the aircraft was leased from International Lease Finance Corp, the leasing unit of U.S. insurance giant AIG

Los Angeles-based ILFC was not available for comment and there was no immediate confirmation of these details.

The A321 is the largest of the A320 family of single-aisle jets produced by EADS subsidiary Airbus. This particular type of aircraft, which can seat up to 185 passengers, has been in service since 1994.

(Additional reporting by Augustine Anthony, Zeeshan Haider, Chris Allbritton and Shiza Shahid in ISLAMABAD; Sahar Ahmed in KARACHI; Tim Hepher in PARIS; Writing by Sanjeev Miglani; Editing by Miral Fahmy and Sugita Katyal)