Millions of Shiite Muslims travel to Iraq to commemorate the death of Imam Hussein

On Saturday, millions of Shiite Muslims gathered through the streets of the Iraqi city of Karbala on their annual pilgrimage to commemorate the death of Hussein, grandson of the Prophet Muhammad. Hussein became a symbol of resistance when he refused to pledge allegiance to the Umayyad Caliphate, leading to his death in battle in the turbulent first century of Islamic history.

Tahseen Al-Khafaji, head of the Iraqi security media cell, said more than three million pilgrims had entered the country by Friday amid tight security.

This year, Arba'in – the Arabic word for the number 40 and traditionally the end of a period of mourning – was marked by mourning over the war in Gaza, which is now in its eleventh month. There are also great concerns that the war could escalate into a regional conflict. Tensions between Israel and Iran have increased after the leader of the Palestinian militia Hamas, Ismail Haniyeh, was killed in an explosion in Tehran last month.

Hussein's death deepened the divide between the two main Islamic sects, Sunni and Shiite. But for many Muslims, that divide has faded into the background as they now share anger and grief over the suffering of Palestinians in Gaza, where more than 40,000 people have been killed.

Pilgrims typically flock from around the world to celebrate Arbaeen on the 20th day of Safar, the second month of the Islamic lunar calendar each year. The climax is the site where Hussein and his half-brother Imam Abbas were killed during the Battle of Karbala, which many see as a reminder of the Shiite community's unity during centuries of unrest.

“May God never take this solidarity away from us,” said Amad Zarepoor, who had traveled from Iran.

On Saturday, the rhythmic sound of pilgrims beating their chests and heads as they circled the Imam Hussein shrine filled the air.

One of the busiest points is the Iraqi-Iranian border crossing of Mandali in the northern Iraqi province of Diyala. Sinan al Shemmeri, a spokesman for the Popular Mobilization Forces, a coalition of predominantly Shiite militias allied with Iran, said the crossing was “not only for Iranian brothers, but also for various other nationalities, such as Azerbaijan and Pakistan.”

Volunteers could be seen lining the nearly 113-kilometer-long road from the Iraqi capital Baghdad to Karbala, offering food to weary pilgrims.

“Everything we offer is to remember and serve our master (Hussein),” said Hussein Ali, a volunteer in Baghdad.

Iranian pilgrim Ali Bagheri expressed his joy at Iraqi hospitality.

“I am a guest of Iraqis again,” he said. “I am very happy that I can walk this path with Iraqis and make a pilgrimage with them.”

Despite the celebrations, this year's Arba'in festival was also marred by a bus accident in central Iran on Wednesday that left 28 passengers dead and 23 others injured, 14 of them seriously.