South Korea is trying to verify reports that a small number of North Korean refugees being held in China is on hunger strike.
The South Korean Unification Minister, Jeong Se-hyun, said the refugees were reportedly being held in the northern Chinese city of Tumen.
They were reported to have begun their protest on Monday, to oppose their forced repatriation to the North.
China has denied any hunger strike is taking place.
Reports have circulated for months that China was rounding up North Korean refugees on its side of the border.
The latest reports, which appeared in several South Korean newspapers, gave varying details about the size and nature of the protests, with some newspapers saying 10 refugees were involved, and others talking of up to 100.
Mr Jeong said sending the North Koreans home against their will would violate humanitarian principles, and they should be allowed to come to South Korea if they wished.
North Korean refugees typically escape through China, which shares a border with the North. If they are able to make it to an embassy in Beijing, then they are often sent to South Korea, usually via a third country.
But thousands remain stranded on the Chinese border - waiting for help to make the dangerous journey to Seoul. If they are discovered by Chinese police, they are almost certain to be returned home. China has a treaty with its ally North Korea which obliges it to send refugees back.