"I announce five days of public mourning and offer my condolences to the dear people of Iran," Khamenei said in a statement. Mokhber, like Raisi, is seen as close to Khamenei. The crash comes at a time of growing dissent within Iran over an array of political, social and economic crises. Iran's clerical rulers face international pressure over Tehran's disputed nuclear programme and its deepening military ties with Russia during the war in Ukraine. Since Iran's ally Hamas attacked Israel on Oct. 7, provoking Israel's assault on Gaza, conflagrations involving Iran-aligned groups have erupted throughout the Middle East.