A group of 29 people identifying themselves as North Koreans have sought asylum in a South Korean school in the Chinese capital, Beijing.
The North Koreans are hoping for asylum in the South
The South Korean news agency Yonhap says the group cut through a wire fence to enter the building, which does not seem to have diplomatic status.
Around 20 people claiming to be North Koreans entered South Korea's consulate in Beijing last week.
Asylum-seekers have been invading foreign missions in China since 2002.
Despite having an agreement with Pyongyang to repatriate such people, the Chinese have allowed many to travel to South Korea through third countries.
The latest group, 23 women and six men, got into the unguarded five-storey building through a rear entrance and crowded into the headmaster's office on the ground floor, Yonhap reports.
According to an unconfirmed report,
classes were in session when the group moved in.
China tightened security after recent invasions of foreign missions
The school, which has 556 South Korean students, immediately
informed the South Korean embassy of the incident and called for support and guidance, Yonhap adds.
"Their entry here has been reported to the embassy and we are waiting for its order," school official Yoo In-hoo was quoted as saying by South Korean cable news network YTN.
An unnamed South Korean diplomat told Reuters news agency the school invasion was a new development for his country.
"We think we need consultation with the Chinese side on this case," the diplomat said.
"We hope the Chinese side will deal with this case as they do with others."
Nine North Koreans who entered the American School in Shanghai in September were handed over to police on the grounds that that school had no diplomatic status.
More than 460 North Korean refugees were airlifted to South Korea in July from Vietnam, in an action which enraged Pyongyang.
But seeking asylum at foreign embassies in China remains a risky strategy for North Koreans, according to correspondents.
As Pyongyang's closest traditional ally, Beijing is loath to take any steps that might destabilise its neighbour or lead to waves of asylum seekers pouring over the border.
So China often deports North Koreans it catches back to their homeland.
It has also thrown heavy security around embassies to try to deter such asylum attempts.
Despite the risks, many North Koreans are still prepared to take the chance and activists estimate that about 200,000 are currently hiding in China.