At least six people were killed and eight others injured when a chartered helicopter of Mari Petroleum Company crashed near Shewa oil field in North Waziristan.The injured have been taken to CMH Thal by helicopter. According to initial reports, the crash was caused by engine failure.An investigation into the accident has been initiated.Meanwhile, Khyber Pakhtunkhwa Governor Faisal Karim Kundi and Chief Minister Ali Amin Gandapur have expressed grief over helicopter crash in North Waziristan.In their separate statements in Peshawar on Saturday, both the leaders expressed sorrow over the loss of precious lives in the incident.They prayed for the departed souls and patience for the bereaved families.They also prayed for swift recovery of the injured.Source: Radio Pakistan