Dozens of North Korean defectors in China were recently arrested and will soon be deported back to their communist homeland, a South Korean humanitarian group said Sunday.

In a special bulletin posted on its own website, the Commission to Help North Korean Refugees (CNKR) claimed a group of 20 North Koreans was rounded up in Shenyang, China, on Sept. 26, along with 10 others in Weihai, Shandong Province, on the same day.

"It has been confirmed that a total of 35, including three on Sept. 29 and two on Sept. 30 in Yanji, have been arrested. They are said to be set for deportation back to North Korea through Tumen in early October," the CNKR said, urging the Chinese government to immediately release the North Koreans.

China, North Korea's largest ally, does not recognize North Korean defectors within its borders as refugees and regularly rounds up North Koreans and deports them back to their communist homeland. Back in North Korea, they are said to face severe punishments ranging from torture to public execution.

The special announcement, dated Friday, also urged the Seoul government and the U.N. High Commissioner for Refugees to work for the release of the North Koreans now in detention in China.

More than 20,000 North Koreans have defected to South Korea since the end of the 1950-53 Korean War, with many of them reaching the South after first fleeing to China.

Human rights activists believe more than 100,000 North Koreans may still be in China in search of a safe route to South Korea. (Yonhap News)