An Iranian passenger plane heading to Tehran crashed Sunday morning in a mountainous rural region. All 66 people on board, 60 passengers and six crew members, are presumed dead. Retrieval efforts have been hindered by the crash site's remote location and bad weather. Iran has a poor record on aviation safety because international sanctions intended to restrain its nuclear development make it difficult to obtain parts to keep planes in good condition. This plane, operated by Aseman Airlines, was 25 years old.

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