Chief of Staff of the Iranian Armed Forces Major General Mohammad Bagheri has assigned a high-ranking delegation to investigate into the case of a helicopter crash in which President Ebrahim Raisi and his accompanying team died.The delegation has been dispatched to the site of the incident and the investigation has already begun, Iran news agency (IRNA) said.The results of the investigations will be announced later when the mission is completed.Iran announced yesterday the death of President Raisi, Foreign Minister Hossein Amirabdollahian and a number of senior officials after their helicopter crashed.