Multi-day state funerals for Iran's Supreme Leader Ali Khamenei have begun in Tehran. The central ceremony is taking place at the Grand Mosalla of Imam Khomeini, where coffins containing the bodies of Khamenei and several family members who died alongside him are displayed. The mourning events will last until July 9 and will cover not only various cities in Iran but also a number of Shia shrines in Iraq. According to Iranian authorities, millions of people are expected to participate in the ceremonies. On the first day alone, thousands filled the streets of Tehran, carrying state flags, portraits of Khamenei, and participating in traditional mourning processions. Despite the hot weather, the flow of participants continues to increase. International agencies report that during the processions, slogans calling for revenge are being shouted, and mourning banners featuring the image of the deceased leader are displayed throughout the city. Particular attention is being paid to security. Authorities have increased the presence of security forces, implemented additional security measures, and closed the airspace over Tehran. Official statements indicate that this is necessary to ensure the safety of mass events and high-ranking participants in the ceremonies. Foreign delegations and representatives from countries maintaining relations with Iran are expected to attend the funeral. The mass gathering of people and the participation of the country's leadership make ensuring security one of the main tasks for the organizers. Additional attention is focused on the possible first public appearance of Iran's new Supreme Leader Mojtaba Khamenei. So far, authorities have not officially confirmed whether he will participate in the main ceremonies. According to Iranian officials, he sustained injuries during the attack that resulted in his father's death. The funeral takes place against the backdrop of ongoing tensions between Iran, Israel, and the United States. Iranian leadership representatives have stated that any attempts to attack during the mourning events will be met with a harsh response. In turn, U.S. President Donald Trump has stated that Washington is pausing negotiations with Iran during the mourning events. The funeral of Ali Khamenei has become the largest state mourning event in Iran in recent decades. It occurs more than four months after his death — such a lengthy preparation was explained by the war and security considerations. The multi-day funeral of Ali Khamenei has become not only the largest mourning event in modern Iran but also an important political event that the entire world is closely watching.