Tehran, Sep 2 (IANS): Severe weather conditions, including thick fog, were primarily responsible for the helicopter crash in May that resulted in the death of Iran's late President Ebrahim Raisi, according to a final investigation report.

The General Staff of Iran's Armed Forces released the report, stating that the technical, engineering, electronic, and navigation aspects of the helicopter were thoroughly examined. The findings confirmed that all procedures and measures adhered to established standards and regulations before and during the flight, Xinhua news agency reported, citing IRIB news agency.

The report ruled out deviations from the flight route, incorrect route information, and external interference as factors in the crash. It also noted that the pilot did not report any emergency situation, and forensic examinations revealed no evidence of foul play or an attack.

The report attributed the crash to the region's "complicated climatic and atmospheric conditions during spring", which led to the formation of dense fog and caused the helicopter to crash into a mountain.

Raisi, along with his entourage, including former Foreign Minister Hossein Amir-Abdollahian, died when their helicopter crashed in a mountainous area in East Azarbaijan province on May 19.