PHUKET, Thailand -- Amid Christmas lights strung along the beachfront, a cluster of mourners bowed their heads toward the ocean at dusk Saturday and offered prayers for the hundreds of thousands killed a year ago in the Indian Ocean tsunami.

On a nearby beach, Thailand's Moken sea gypsy tribe banged drums and chanted as offerings of candles, flowers and incense wrapped in banana leaves were pushed out to a gently lapping sea in a ceremony to ward off evil spirits.

The two commemorations were a somber, low-key start to events marking one year since the Indian Ocean rose up in a massive, earthquake-spawned tsunami that left at least 216,000 people dead or missing in a dozen countries.

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.

No such progress was made in Sri Lanka, where disputes over aid delivery and an upsurge in violence blamed on separatist Tamil Tiger rebels dashed hopes for an end to a long-running civil conflict. Bloodshed continued Saturday as two government soldiers were shot, one fatally, and troops returned fire, killing five rebels.

A year ago Monday, a massive magnitude-9 earthquake ripped apart the ocean floor off Sumatra, 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 whole islets in the Maldives temporarily disappeared.

At least 216,000 people were killed, according to an assessment of government and relief agency figures by The Associated Press. The United Nations puts the number at 223,000 or more.

The true toll probably never will be known -- many bodies were lost at sea and in some cases the populations of places struck were not accurately recorded.

Almost 400,000 houses were reduced to rubble and more than 2 million people left homeless, the U.N. says.

The world responded with some $13.6 billion in pledges. Rebuilding has started in some places, and fishing boats and seeds have been handed out to kick-start ruined village economies.

But many refugee camps are still full and their residents rely on handouts to survive.

"It's been a tough year, if anything things have gotten worse as things went on," said Nila, a 42-year-old Indonesian woman who lost three of her four children to the waves. "I somehow feel lonelier."

On Thailand's Bang Niang beach, hundreds of people took part in the Moken ceremony, many with scraps of cloth pinned to their backs bearing handwritten messages of support for those who survived the tragedy.

Peter Pruchniewitz, 68, who was swept from his hotel room and lost a friend to the waves a year ago, returned from Zurich, Switzerland, for the ceremony. Asked why he came back, he said simply, "To remember."

On an open-air terrace at a hotel on Patong beach, more than 50 Britons observed a moment's silence and were led in prayers at dusk.

There were also signs that the legendary bustle of Phuket island's beach and nightlife was returning to normal. The entire arc of the beach was strung with Christmas lights, and Thai hotel workers dressed as Santa entertained Western tourists nearby.

Final preparations were being made for hundreds of commemoration ceremonies Monday, and the tsunami was expected to feature in Christmas prayers Sunday across the region.

In the Indonesian provincial capital of Banda Aceh, workers on Saturday scaled the minarets of a 16th-century mosque to replace missing tiles and slap on a fresh coat of whitewash.

Thousands of survivors have been rehoused in Aceh, but agencies say they are only about 20 percent of the total number needing new homes. The landscape in many places is still one of devastation.

Former President Clinton, the U.N. special envoy for tsunami recovery, said the international community faced a "critical challenge" in following through on its promises of help.

"Millions of ordinary people across the globe rallied to the immediate aid of communities devastated by the tsunami," Clinton said in remarks published Saturday in the International Herald Tribune. "Now our collective challenge is to finish the job, to leave behind safer, more peaceful and stronger communities," he said.

Associated Press reporters Meraiah Foley and David Longstreath in Thailand; Chris Brummitt in Banda Aceh, Indonesia; and Dilip Ganguly in Colombo, Sri Lanka, contributed to this report.