Heavy rains and flooding in Putumayo, south-western Colombia have put nearly 16,500 families at risk.
Armed conflict and the presence of thousands of landmines means Putumayo is already a dangerous place to be a child. Now, the floods have displaced landmines so there's an even higher risk of a child stepping on one.
UNICEF is asking for £1,560,000 to provide protection, education, water, sanitation and hygiene, health and food for families.
Flooding and risk of landmines means thousands of children are unable to attend school. It also makes it difficult to transport food, which has led to a severe shortage.
Children are at risk of disease because of contaminated water sources and poor sanitation.
In some areas, children are also in danger of recruitment, abuse and exploitation by illegal armed groups.
"The impact of this emergency on children is double," said Viviana Limpias, UNICEF deputy representative. "Hostility and the effects of the flooding mean they fear both stepping on a flood-displaced landmine and being recruited by an illegal armed group."