VAVUNIYA, Sri Lanka (CNN) -- After visiting a displacement camp in Sri Lanka on Saturday and flying over the site of the last battle in the country's recently ended civil war, U.N. Secretary-General Ban Ki-moon called the sites "appalling."
Internally displaced Sri Lankan watch through barbed wire during a visit by the U.N. secretary-general.
"I have traveled around the world and visited similar places, but this is by far the most appalling scenes I have seen," Ban told CNN. "I sympathize fully with all of the displaced persons."
Ban called for better humanitarian aid after interviewing some of the people regarding shortages of water and medicine.
Ban toured Manik Farm, a sprawling camp for internally displaced people in the country's north, days after Sri Lanka declared victory in a 25-year civil war against the Tamil Tigers rebels.
About 250,000 to 300,000 people are refugees in the country, according to humanitarian groups and U.N. figures. Some in the camp have experienced fierce fighting in recent months, saying they did not believe at points that they were going to survive.
"I have seen the complete devastation here, and there must have been in the crossfire many civilian casualties. There simply must have been," Ban told CNN's Sara Sidner.
The Sri Lankan government has said it doesn't believe many civilians were injured or killed in the fighting.
While the war's end elicited celebrations in some parts of the country, humanitarian groups and the United Nations worry over those uprooted by the fighting. Ban arrived in the South Asian island nation Friday, saying he came to offer help and partnership.
"I hope my visit today can help begin a process of national recovery, renewal and reconciliation for all Sri Lankans," Ban said in a written statement issued Friday. "That is why I am here."
Ban met with Sri Lankan President Mahinda Rajapaksa and asked that humanitarian organizations be given unrestricted access to provide more aid to the displaced. The president seemed open to the idea, Ban said.
Ban said earlier he would urge the government to expedite the screening and processing of refugees and ensure that displaced camps have adequate supplies of food, medicine and water.
CNN's Sara Sidner contributed to this story.