By Sui-Lee Wee and Megha Rajagopalan
BEIJING (Reuters) - China is sending civilian militias to help secure the border it shares with North Korea, state media said, in the wake of two reported killings of Chinese citizens by North Koreans that could strain ties between Pyongyang and its sole major ally.
The China Defence News said on Wednesday the government had established a civilian-military defense system in the Yanbian prefecture of Jilin province. Yanbian shares a border of about 500 km (310 miles) with North Korea.
"China and North Korea are both keeping guard on the border ...," the newspaper said. "The situation is more complicated and relying on just one party would make it difficult to achieve effective control."
The government has also "guided the establishment of militia patrols" to guard border villages. Every 10 neighboring households would have their own border security group and there would be 24-hour video surveillance, the newspaper said.
Last week, China said it had lodged a protest with North Korea after media reported that a North Korean army deserter had killed four people during a robbery in the Chinese border city of Helong late last month.
State media has raised questions about the China-North Korea relationship, saying that the Chinese government "should not be too accommodating".
The issue of border security has become "very serious", said
Zhang Liangui, a North Korea expert at China's Central Party School.
"The fact that North Koreans are running over the border to China shows that North Korea's regulation of the border is seriously problematic," he said. "They have neglected it."
While it is too early to determine if there will be a longterm impact on diplomatic ties, the situation raised tension near the border, he added.
"For those Chinese citizens living near the border, there is widespread anxiety right now, the impact of the situation is very serious," he said. "To say that this will have no impact on relations with North Korea just doesn't match with reality."
China is North Korea's most important diplomatic and economic ally, although three nuclear tests, several rounds of saber-rattling and violence on the China-North Korea border have tested Beijing's support.
The 520 km-long Tumen River that divides China and North Korea is a popular route used by defectors fleeing the secretive North.
(Editing by Paul Tait and Clarence Fernandez)