Amid the Christmas lights strung along a beach front in Thailand, a cluster of mourners bowed their heads toward the ocean at dusk on Saturday and offered prayers for the hundreds of thousands killed one year ago in the Indian Ocean tsunami. Hours earlier on a beach nearby, Thailand's sea gypsy tribe, the Moken, played drums and chanted as offerings of candles, flowers and burning incense wrapped in banana leaves were pushed out to a gently lapping sea in a ceremony to ward off evil spirits. The two ceremonies marked a somber, low-key start to events marking the first anniversary since the Indian Ocean rose up in a massive earthquake-spawned tsunami that left at least 216,000 people dead or missing in one dozen countries last December 26. At sites around the ocean's rim, officials, survivors and relatives of the dead prepared to mark the grim anniversary from Thailand where life is returning to normal, to graveyards in Indonesia's Aceh province where the rubble is still piled high. The mourning comes as survivors and officials take stock of the massive relief operation and peace processes in Sri Lanka and Aceh, the two places hardest hit by the tsunami. Success has been mixed. In Aceh, the tsunami resulted in a cease-fire between the government and guerillas to end a decades-old separatist conflict. However, no such progress was made in Sri Lanka where disputes over aid delivery and an upsurge in violence blamed on separatist Tamil Tiger rebels have dashed hopes that the tsunami would bring a final end to the country's long-running civil conflict. Troops patrolled the streets of the capital city of Colombo on Saturday to provide security for tsunami ceremonies. The massive magnitude-9 earthquake ripped apart the ocean floor off Sumatra Island, displacing millions of tons of water and sending giant waves crashing into Indian Ocean coastlines from Malaysia to east Africa. A dozen countries were hit. Entire villages in Indonesia and Sri Lanka were swept away, five-star resorts in Thailand were swamped, and in the Maldives whole islets temporarily disappeared.