A key British figure in the tsunami recovery effort has criticised the way aid was spent on the tenth anniversary of the natural disaster.
Lilianne Fan said problems with aid management in parts of Indonesia had created risks of renewed fighting in communities, while homes built with donor money lay empty and unemployment persisted.
Around 170,000 Indonesians died in the 2004 Boxing Day tsunami and around 500,000 were made homeless, according to the Overseas Development Institute (ODI).
The institute said that while Aceh was the worst-hit province its recovery is often hailed as a success story - yet it is still one of the poorest parts of Indonesia.
Ms Fan, a British- Malaysian, has worked in the region for 15 years and now works in London as an ODI research fellow. During the tsunami response she worked in the governor of Aceh's advisory team and has returned to the area for the anniversary.
Ms Fan said that while money dried up soon after the disaster struck, the region is often exposed to disaster and still being devastated.
Speaking on Christmas Eve, she said there were at least 25,000 people displaced because of flooding today alone .
She said: "The fact that so much aid came into Aceh (when the tsunami hit) means a very stark lack of donation and development aid now. Donors feel they have given enough so they shouldn't give any more."
She said this was both from institutional donors, such as the EU, and public aid - including that from the UK.
Donor funding fell dramatically four or five years after the tsunami - from seven billion US dollars (£4.5bn) to almost nothing now - and Ms Fan said even getting funding for a sustainable development plan was incredibly difficult.
According to the researcher, this was partly caused by sensationalism and public pressure to spend the money immediately.
She said: "The humanitarian side was very important and really well done ... but three years after a disaster you should not be giving out enormous cash grants. That does not help livelihoods. It's not life saving at that point.
"How do you ensure you're not creating a dependency on aid as well?
"The Indonesian government did a tremendous job in terms of their role as co-ordinator but they couldn't co-ordinate the funding because agencies had raised so much money independently they really did have the final say."
Ms Fan said that many organisations focused on building housing but thousands were now abandoned because residents had left to search for work.
According to the ODI, many new housing developments have become ghost villages and property on 150km of Aceh's western coast - which cost 250 million dollars (£161m) in US aid - remains mostly unused.
Ms Fan said: "You do feel that people are very grateful for all the aid that has been given but if you look beneath the surface there are other issues. For somebody that has been involved as long as I have I can't ignore these issues."
The former aid worker also raised concerns of renewed violence in Aceh. T he Indonesian province was devastated by three decades of violent armed conflict before the natural disaster, but while funding poured into tsunami-hit parts, Ms Fan said the conflict areas were ignored.
She said: " Suddenly you have seven billion US dollars going into one part of the country but not into another. You're creating very clear inequalities, that's created resentment because the economy is very stagnant in some areas."
She warned that the risk of new conflicts should not be underestimated. "They haven't benefited from aid of any kind - they do feel very frustrated... This is a society which has gone through decades and decades of war - they're quite ready to take up arms again," she said.
She added that aid agencies - the UN particularly - should have made people more aware they were putting money into an area affected by conflict.
Ms Fan said : "The whole humanitarian sector needs to think a lot more carefully about the way they think about humanitarian disasters in areas of conflict - m aking sure we are not creating new problems. The problem isn't that it's difficult, it's that people didn't think about it."
The former aid worker said what the region needed now was support through its current condition. " Engagement is needed - it's not necessarily aid," she said.
"It's not to say the aid wasn't needed. It was. But if you look 10 years on, people are still struggling with their livelihoods and that's something that should have been done to support economic recovery."