Islamabad, May 9 (IANS): Pakistan’s Air Chief Marshal Sohail Aman on Saturday said the Mi-17 helicopter which crashed on Friday killing two foreign envoys, spun out of control due to a mechanical fault moments before landing.

The air chief said that the helicopter's behaviour was normal just prior to landing when it suddenly went out of control, Geo News reported.

"Our base commander had eye contact with the helicopter and there was no problem in its behaviour. The helicopter lost control just moments before landing," he said.

The Mi-17 helicopter crash-landed on a school in Naltar valley near Gilgit Baltistan. It was carrying 17 people - 11 foreigners and six Pakistanis.

Among the victims were Ambassadors Domingo D. Lucinerio Jr. of the Philippines and Leif Larsen of Norway and the wives of the Malaysian and Indonesian ambassadors and three Pakistanis -- two pilots and one crew member. Dutch Ambassador Marcel de Vink and Polish Ambassador Andrzej Ananicz were injured in the incident.

According to Aman, an investigation has been started and there would be a detailed analysis of the crash.

He added that the pilots flying the helicopter were "proficient and excellent" and had made several flights in that area.

Ruling out the possibility of any terrorist activity, Foreign Secretary Aizaz Chaudhry said the crash happened due to engine failure.