ISLAMABAD (AP) — A passenger jet carrying 152 people crashed into the hills surrounding Pakistan’s capital on Wednesday morning, officials said. Rescuers were trying to reach the scene amid rain and difficult roads.

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.

“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 some bodies, police official Mohammad Saeed said. The army said it was sending special troops to the area to help out along with helicopters.

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.

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.