Christmas in 2004, a 9.1 magnitude earthquake triggered tsunami waves that killed some 230,000 people across a dozen countries.

Survivors and mourners gathered at mass graves in Indonesia, Thailand and other places along the Indian Ocean that were devastated by the 2004 tsunami — the deadliest in the world.

The powerful 9.1-magnitude earthquake off the coast of the Indonesian island of Sumatra, triggered a tsunami that killed around 230,000 people across a dozen countries.