Thousands of survivors and mourners across Asia marked the two year anniversary of the devastating tsunami by visiting mass graves, lighting candles along beaches, observing a moment of silence and erecting warning towers in hopes of saving lives in the future.

Some volunteers were replanting mangroves, saying they were key to protecting coastal communities.

The magnitude 9.0 earthquake that ripped apart the ocean floor off Indonesia's Sumatra island on December 26, 2004 spawned giant waves that fanned out across the Indian Ocean at jetliner speeds, killing people in a dozen countries and leaving millions homeless.

"Ever since the tsunami, my brother has done nothing but drink," said Nagarwali, 42, pointing to a man who lost his wife and three children in the waves.

Nearly 167,000 of those killed were from Aceh province - hundreds of kilometers (miles) from Bali - where tens of thousands of people still live in temporary homes.

The 2004 tsunami generated an unprecedented outpouring of generosity, with donor pledges reaching some US$13.6 billion (euro10.31 billion).

International relief agency Christian Aid has so far built more than 20,000 new permanent homes and helped more than 185,000 people back to work since the tsunami.

Altogether Christian Aid helped 290,000 people in 2006 and since the tsunami has spent more than £29m in India, Indonesia and Sri Lanka on water, food, medicines, housing and training. Another £13m will be spent by the end of 2007.

In addition, nearly 8,400 fishing boats have been repaired, while 53,000 people have received trauma counselling.