Ceremonies were held in countries across Asia on Thursday to remember the more than 220,000 people who were killed two decades ago in the Indian Ocean Tsunami, the most deadly tsunami in history. On 26 December 2004, a 9.1-magnitude earthquake struck Indonesia’s Sumatra island, triggering huge waves that slammed into coastal communities across the Indian ocean. The waves, which towered as high as 30 metres, killed 227,899 people across 15 countries. In Indonesia’s Aceh province, the worst hit area, a siren rang out for three minutes at the Baiturrahman Grand Mosque on Thursday morning, after which Islamic prayers were held.