Chinese police detained 65 North Korean asylum-seekers (search) in Beijing, South Korean activists said Wednesday, accusing China (search) of carrying out "hardline measures" to round up refugees from its ally North Korea.

Two South Korean human rights activists also were detained in the raid Tuesday on two houses on the Chinese capital's east side, South Korea's Yonhap news agency reported.

The detentions came amid a surge in large-scale asylum bids in recent weeks. Scores of North Koreans are in the Canadian and South Korean Embassies and other foreign facilities in Beijing, waiting for permission to leave for South Korea.

A woman who answered the phone at the Beijing police spokesman's office wouldn't confirm the reports. But a Beijing newspaper said police detained more than 60 "illegal immigrants" on Tuesday as they prepared to enter the South Korean Consulate.

"This move shows that the Chinese government has begun implementing its hardline measures and started a wide-scale roundup operation against people who have fled North Korea," said a statement by the Seoul-based Civil Coalition for Human Rights of the Kidnapped and Defectors from North Korea (search).

Another Seoul-based group, the Democracy Network Against North Korean Gulag, said the detained activists were two of its members. It said they were born in North Korea but escaped to the South. The group wouldn't give their names but Yonhap identified them as Kim Hong-kyoon, 41, and Lee Soo-chul, 47.

China appealed Tuesday to foreign embassies to stop giving refuge to North Koreans, saying they are economic migrants led by activists with "ulterior motives."

Thousands of North Koreans fleeing famine and repression have been allowed to leave for the rival South over the past three years after seeking refuge in embassies and other foreign offices in China.

But China still tries to block asylum attempts and have detained scores of people. Beijing is obligated by treaty with its allies in Pyongyang to send home fleeing North Koreans, though it isn't known to have done so in cases that become public.

In the biggest asylum bid to date, 44 North Koreans entered the Canadian Embassy in September by climbing over a spiked fence. They are still waiting there.

On Monday, three people believed to be North Koreans entered a South Korean Consulate building in Beijing while others were detained. Dozens of other North Koreans already are in South Korean diplomatic offices.

"We hope these embassies will refrain from providing refuge to those illegal immigrants," Chinese Foreign Ministry spokeswoman Zhang Qiyue said Tuesday.