Team Rubicon UK, made up of ex-military personnel, are helping communities in the Sumur region of Indonesia following a devastating tsunami.
At least 400 people were killed when a volcanic eruption sent two waves up to five metres high surging into the Sunda Strait on 22 December.
The tsunami wrecked hundreds of communities along the west coast of Java and south Sumatra.
On Christmas Eve, five Team Rubicon UK volunteers spent their day preparing equipment before flying out to Jakarta on Christmas Day.
The team are helping with recovery operations and providing damage assessments by drone.
Team Rubicon UK deployed to the area with water purification units to provide clean, safe water to thousands of people.
Paul Taylor, Operations Support Manager on the ground, said: "We are now identifying where the people are with the most need – those large concentrations of displaced people – and we will provide them with the critical asset that is clean water.”