Provinces in southern Thailand have held memorial services in various locations along the western coast that was hit by giant waves that killed more than 5300 people, including Australians, 11 years ago.
Anniversary events were held at Kamala Memorial Stone, Mai Khao Memorial Wall, Phuket City Hall and Patong Beach in the southern resort island of Phuket.
Interfaith ceremonies were also held in resort towns across the Andaman coast from Phang Nga province to Phi Phi archipelago.
Many relatives from abroad who lost their loved ones in the December 26, 2004 tsunami travelled to Thailand to join the service.
The tsunami struck during peak tourist season at the beaches and islands in Thailand, killing thousands of holidaymakers as well as workers and villagers.
Thailand was one of the countries hit by the tidal waves from a 9.1-magnitude earthquake off the coast of Indonesia's Sumatra island.
On December 3, Prime Minister Malcolm Turnbull unveiled a memorial for the 26 Australian victims in Canberra.
Mr Turnbull said it was a place where he hoped grief could give way to commemoration.
"They may be buried in different places, but their lives are forever bound through that one fateful moment," he said.
The tsunami spread despair and destruction across 14 countries around the Indian Ocean and left a death toll of more than 225,000. It was the deadliest tsunami in recorded history.
Mr Turnbull also paid tribute to the nine defence force personnel who were killed in a helicopter crash on the Indonesian island of Nias during humanitarian efforts in the catastrophe's aftermath.
"We cannot speak of the tragedy of the tsunami without also speaking of those who responded with such courage and selflessness," he said at the event.
In Aceh, where the tsunami killed at least 165,000 people in Indonesia's westernmost province, Governor Zaini Abdullah and regional officials visited a mass grave for the victims, and then attended a memorial religious service at a mosque.
Fishermen marked the tragedy by abstaining taking their boats out on Friday and Saturday.
"Fishermen were advised not to go fishing for two days in remembrance of the tsunami and because it was Friday," Miftah Cut Adek, a community leader was quoted by news website Detik.com.
The powerful undersea earthquake that struck about 160 kilometres off the western coast of Sumatra island generated giant waves that devastated coastal areas in Aceh. Victims included 37,000 injured and about half a million displaced people.
The tidal waves also caused death and destruction in India, Thailand, Malaysia, Sri Lanka and elsewhere in the Indian Ocean, including coastal Africa.
