TEHRAN – Hundreds of thousands of Iranians gathered in main squares across the country on Monday evening to mourn the martyrdom of Leader of the Islamic Revolution Ayatollah Seyyed Ali Khamenei, who was assassinated in U.S.-Israeli strikes over the weekend, as national organizations called for continued demonstrations of unity.
Worshippers assembled after evening prayers in major Tehran thoroughfares including Vali-e Asr Square, Haft-e Tir Square, Sadeghieh Square, Monirieh Square and Vanak Square, witnesses said. 
Mourners carried Iranian flags and pictures of the late leader, chanting “Death to America” and “Death to Israel.”
The Cultural and Artistic Organization of Tehran Municipality announced it would host gatherings nightly from 7 p.m. to 11 p.m. at Vali-e Asr Square, featuring group anthems, elegy recitals and cultural programs. The organization described the events as aimed at strengthening social solidarity and encouraging public participation in a spiritual and epic atmosphere.
One participant told official news agency IRNA: “They martyred the Leader of the Revolution thirsty, just like Imam Hussain, and we, the Muslim nation, will take severe revenge on the enemies.”
Another Tehran resident said: “The Leader of the Revolution knew the enemies of this country, like America and Israel, well, which is why the enemies martyred the Leader of the Revolution in this way. The blood of the martyrs will never be wasted, and the nation will take severe revenge.”
The Islamic Propagation Coordination Council issued a statement calling for further gatherings on Tuesday evening at 8 p.m. in main squares across the country and in Tehran’s Enghelab Square, with the participation of religious groups.
In its statement, the council described Imam Khamenei as a “mujahid jurist and divine reference” whose martyrdom has wounded the hearts of monotheists worldwide. It likened his martyrdom to that of Imam Hussain (AS), the Shia martyr, stating that the enemy martyred him thirsty in the fasting month of Ramadan.
“The wise nation of Iran knows well that two truths are eternal; the supreme essence of God and Imam al-Asr (the hidden Imam),” the statement said. “The banner of this revolution will be handed over to someone who will continue
 this luminous path with firmness. The martyrdom of this pure soul is not the end of the road, but the beginning of another victory.”
The council added that the blood of the late leader would unite the nation and pave the way for the establishment of a global government of justice under the twelfth Shia Imam, promising that popular gatherings would continue as long as necessary.
Similar processions were held in cities across the country, with images showing crowds filling streets under strict security measures. The gatherings mark the largest public demonstrations since the strikes began three days ago.