CNN said Saturday the blaze began with a cooking accident in the camp, which is located in Mae Hong Son province in northwestern Thailand.
"We are deeply saddened by this tragic incident and doing what we can to provide instant relief," said Mireille Girard, a representative for the United Nations refugee agency in Thailand.
The encampment was originally built in 1992 to house refugees who fled ethnic violence in Myanmar, which has been ruled by a military junta since 1962.
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