Hundreds of thousands of people were killed in the devastating Indian Ocean tsunami two decades ago, and countries around Asia staged ceremonies to mourn them. People gathered in prayer and visited mass graves across Indonesia, Thailand, Sri Lanka, and India to commemorate 20 years since 228,000 people died in one of the deadliest natural catastrophes in human history, when 30m-high waves swept through a dozen nations.

On December 26, 2024, a huge earthquake off the coast of Sumatra, Indonesia, generated a tsunami that reached as far as east Africa. Approximately 1.7 million people were displaced, the majority of them were in the four worst-affected nations, with Indonesia recording the highest number of deaths at more than 170,000.

Today, many wept as they left flowers at a mass grave in Ulee Lheue hamlet, where over 14,000 unidentified tsunami victims are buried. It is one of several mass graves in Banda Aceh, the capital of Indonesia’s northernmost province, which was one of the regions worst devastated by the tragedy.

Hundreds of people gathered to pray at the Baiturrahman mosque in downtown Banda Aceh as sirens sounded for three minutes to mark the time of the earthquake. Muhamad Amirudin, who lost two of his children and has never found their bodies, told the Associated Press that they miss them and do not know where they are.