Pakistan International Airlines flight PK-661 crashed after one of its two turboprop engines failed en route to Islamabad killing everyone on board, authorities said on Thursday, even as they began a probe into the accident and sent bodies for DNA test to identify the victims. The flight with 47 people, including pop singer-turned- Islamic preacher Junaid Jamshed, his wife and deputy commissioner Chitral Osama Warraich, on board crashed in Saddha Batolni village near Havelian on Wednesday while en route to Islamabad from Chitral in Khyber-Pakhtunkhwa province. Saigol said that the aircraft passed an A-check certification in October conducted after every 500 hours of flight operation. He also said that there…