The Foreign Ministry on Wednesday pledged to make all diplomatic efforts to prevent 29 North Korean defectors being deported from China back to their repressive home country.

On July 15-17, the defectors and six of their South Korean helpers were arrested in Qingdao and Kunming in China.

A ministry official declined to disclose the identity of the defectors, citing safety concerns.

The defectors were arrested while hiding in Qingdao or traveling on an established escape route to Southeast Asia with a view to reaching South Korea. They have already been taken to a detention center in the town of Tumen on the border with North Korea.

A staffer of an agency helping defectors said, "Chinese authorities may have wanted to move them quietly to the border and deport them before anyone notices, so this is making things awkward for Beijing."

But South Korean government officials have not been able to interview the South Korean helpers, who include Na Su-hyun (39), himself a defector who now has a South Korean passport. Seoul and Beijing have signed a consular agreement, but it has yet to take effect.

A relative of one of the defectors said, "The Tumen detention center is stopping the families from speaking to them. If they're deported to the North, they'll definitely be sent to a concentration camp."

The defectors, most of whom are of families, left Cheongjin and Musan, North Hamgyong Province or Hyesan, Ryanggang Province in June and July. They include a couple in their 60s and a one-year-old baby girl.