Tens of thousands of new arrivals into Kibati camp in eastern Congohave fled the fighting with just the clothes on their backs and are desperately in need of help.
Outside the camps, many people are having to sleep in the open with no protection from heavy rains.
One woman in Kibati camp told ActionAid: "It is bad enough not to have food, but its worse when the nights arrive and you don't have anywhere to sleep. We lie on these rocks, get rained on and sit in the sun to dry during the day."
Alpha Sanko ActionAid's Director in Congo, said: "We are extremely worried that we may soon have to deal with the larger crises of diseases and epidemic break-outs as people are sleeping in the open in the pounding rains. The lucky ones are finding somewhere to sleep in schools and churches in Goma town, but many others are not so lucky."
ActionAid is helping 50,000 people in the area with food supplies - beans, maize flour, salt and cooking oil and emergency relief items such as soap, mattresses, blankets, plastic sheeting, water containers, mosquito nets and cooking utensils.
"We are concentrating our relief operation in Goma town as well as camps outside Goma. At the same time we are carrying out needs assessments in the region - a task made particularly difficult by the constant movement of people," Mr Sankoh said.
"The humanitarian response is under severe strain with people arriving daily into the camps and Goma town," he added.
In the coming days ActionAid staff will scale up the provision of supplies to more people as they are able to source items and transport them to the camps.
ActionAid is particularly worried about the safety of women and children both inside and outside the relief camps.
Audry Shematsi ActionAid's Women's Rights Coordinator in Goma, said: "We know women are the first target of both soldiers and civilians when law and order breaks down and many remain silent for fear of reprisals or discrimination."
ActionAid is supporting women's groups in Goma and providing counselling for women and children.
Last week delegates from women's groups in Goma visited Kigali, the capital of Rwanda, to present letters pleading for peace to the Rwandan government.
Rwanda has been accused of backing renegade general Laurent Nkunda, who is fighting the Congolese army.
For further information contact:
Anjali Kwatraon 0044 (0) 20 7561 7633 or 00 44 (0) 7941 371357.
ActionAid is an international anti-poverty agency working in over 40 countries taking sides with poor people to end poverty and injustice together