The head of an American human rights group says between 15 and 20 North Korean defectors seek asylum in the United States.

In an interview with Radio Free Asia Friday, Judy Wood of the Human Rights Project said the defectors sneaked into the United States after leaving South Korea, where they had lived for a time.

She did not mention the reasons for the defectors' flight to the United States, but Yonhap News Agency in Seoul said several had openly accused South Korea of oppressing them under its "sunshine policy" of engaging North Korea.

North Korean defector Ma Young-ae in 2004 became the first defector to seek asylum in the United States after resettling in South Korea. Washington is expected to rule on her case by the end of the month.

The United States has thus far rejected asylum requests from North Koreans who have settled in South Korea.

The National Intelligence Service in Seoul says that of 27 defectors who sought to move to the United States since 1997, nine have received asylum.