Chinese authorities are forcing back into Myanmar some of the ethnic Kachin refugees who have fled into China trying to escape civil war, and Beijing is denying basic care to many who remain, a human rights group said on Tuesday.
Myanmar's government is in talks with Kachin rebels, and more than a dozen armed or political groups, to try to end all its decades-old conflicts.
The Kachin conflict, which flared up in the middle of 2011 after a 17-year truce, has pushed up to 10,000 people to seek refuge across the border in the southwestern Chinese province of Yunnan.
New York-based Human Rights Watch said many of these people have little access to proper sanitation, shelter, healthcare or schools for their children.
Others have been detained, refused entry to China or even forced back into the conflict zone in the former Burma, it said in a report.
"The Chinese government has generally tolerated Kachin refugees staying in Yunnan, but now needs to meet its international legal obligations to ensure refugees are not returned and that their basic needs are met," said Sophie Richardson, the human rights group's China director.
"China has no legitimate reason to push them back to Burma or to leave them without food and shelter."
Human Rights Watch said it had documented two cases involving some 300 people who were ordered to return to Myanmar, and others who were sent back into the conflict zone after being turned away at the border.
China's Foreign Ministry did not immediately respond to a faxed request for comment.
However, a Yunnan official said in March that authorities had been providing humanitarian help to the displaced and had helped mediate talks between the rebels and Myanmar's government.
While China has strong business and trade ties with Myanmar, it has long looked with wariness at its poor and unstable southern neighbour, and has repeatedly called on the country to ensure stability along their vast and remote border.
Diplomats say the Kachin conflict is one of the biggest tests for Myanmar's new civilian government's reform effort.
As a signatory to various international conventions on refugees, China has an obligation to properly protect these refugees, but it has not even allowed in the United Nations or international aid groups, Human Rights Watch added.
"Many Kachin refugees have already endured terrible abuses and war in Burma, only to settle into a life of dire struggle in Yunnan," Richardson said.
"Until it is safe for the Kachin to return home, the Chinese government has a responsibility to ensure their safety and well-being."