For more than a month, war has raged in a remote area of northern Myanmar between ethnic Chinese rebels and Myanmar government forces. The fighting, which came after five years of calm, has left several hundred soldiers and insurgents dead -- and is now spilling beyond Myanmar's border.
On Friday, a Myanmar air force plane strayed over the border and dropped a bomb in China's Yunnan province, killing four people in a sugar cane field and injuring nine others, China said, though a Myanmar official later said the bomb did not come from a government warplane.
Last weekend, another bomb also landed in Chinese territory, damaging a house. Tens of thousands of refugees have crossed from the Kokang region of Myanmar into China, many sheltering in camps set up by the Chinese Red Cross.
The fighting has placed Chinese leaders in Beijing in an increasingly awkward position. The Kokang rebels speak Mandarin and have deep commercial and personal connections in Yunnan. Many ethnic Chinese in the Kokang region complain of being treated like second-class citizens by their own government, and the rebels are fighting for more autonomy from the central government.
But China has for years insisted that it adheres to a policy of non-interference in other countries' "domestic affairs" -- and insists other nations do likewise. (The stance is aimed as much at deflecting foreign criticism of China's human rights record and other issues as at preventing China from stumbling into misadventures abroad.)
Chinese authorities also view Myanmar as a strategically significant neighbor with abundant natural resources and access to the Indian Ocean. With Myanmar's recent nascent steps toward democratic reform bringing closer ties with Western countries including the U.S., China is eager to keep amicable relations -- and strong influence -- with its southern neighbor.
China says it has not lent any official backing to the rebels in the fighting that began Feb. 9. But Myanmar's chief of military affairs and security, Lt. Gen. Mya Htun Oo, said last month that rebels were recruiting former Chinese soldiers as mercenaries. Myanmar's information minister, U Ye Htut, called on Beijing to rein in local Yunnan officials who might be offering support.
After Friday's deadly bombing in the city of Lincang, China's vice Foreign Minister Liu Zhenmin summoned Myanmar ambassador Thit Linn Ohn and lodged a complaint.
But Zaw Htay, director of Myanmar's presidential office, told Japan's Kyodo News agency on Saturday that after analyzing data provided by China, the Myanmar military concluded that its warplanes did not carry out the strike. He did not, however, directly blame the bombing on rebel forces.
In a commentary, the state-run Xinhua News Agency said the bombing had "made it all the more imperative for Myanmar to honor its commitment to safeguarding peace and security on the border area to avoid a spillover of its war fire." China's air force also sent planes to patrol the border.
But the commentary added that "the conflict in northern Myanmar [is] the country's internal affair and the Chinese side has always respected Myanmar's sovereignty and territorial integrity .… China hopes the conflict can be resolved peacefully as soon as possible."
Overall, it was a relatively restrained reaction from Beijing, which often responds with much more umbrage to less provocative moves from neighbors such as Japan that it sees as infringing upon Chinese territory.
The rebels' leader, Peng Jiasheng, 85, has taken to social media to appeal to all those of "common race and roots" for support. But China's state-run media have devoted only limited attention to the situation, and Chinese censors have blocked online images showing casualties in an apparent bid to prevent nationalist sentiment from growing too strong.
Wei Tingting, a native of Kokang now living in Nansan town in China, said in a phone interview that bullets often come flying onto the Chinese side; during the phone call she said she heard three explosions and could see smoke rising in the distance.
Chinese police have instructed people in Nansan not to post photos of refugees or other images related to the conflict online, Wei added, and have restricted locals' access to the refugee camps.
"Last time I tried to go to the camps, officials stopped me and gave me a phone number for the Red Cross, and so far I haven't been able to get through to them," Wei said. Some refugees, she added, had recently been urged by Chinese authorities to return home. "It seems [Chinese officials] just want to get rid of the problem," she added.
Li Jiheng, Communist Party secretary of Yunnan province, said last week in Beijing that more than 60,000 Burmese have entered the border area since February. China, he said, had offered temporary accommodation to more than 14,000 and supplied food, water and medicine to them. Others are staying in hotels, apartments or with friends.
The rebels call themselves the Myanmar National Democratic Alliance Army. From 1989, Peng had controlled the region when a self-administered zone was set up -- but he lost control after fighting broke out in 2009. He went into hiding, recently re-emerging.
Min Zaw Oo of the Myanmar Peace Center in Myanmar's capital, Yangon, said Peng's forces were in shambles after 2009, but after receiving fresh access to funding, he began rebuilding. "From 2012 to 2014, there has been a massive build-up of his military," said Min Zaw Oo. "and his forces have multiplied tenfold in two years." Two other small rebel groups in the area have lent support.
The rebels now have 1,500 to 2,000 fighters and are equipped with Chinese-made versions of AK-47s, rocket-propelled grenades and mortars, added Min Zaw Oo, who described the fighting around Kokang's capital, Laukkai, as "trench warfare." "It is not Beijing's policy to arm the rebels," he said, "but individuals from local Chinese military units and also local Chinese officials and businessmen may be involved."
A report in the Hong Kong's South China Morning Post last week, quoting an unnamed source, said that Maj. Gen. Huang Xing -- one of 14 Chinese generals detained in recent months for alleged corruption -- was accused of violating military discipline by leaking state secrets to the Kokang rebels in 2009.
A new pipeline of Chinese-made weapons into Myanmar could undermine the country's ongoing cease-fire talks and spell more instability as the nation prepares for elections later this year.
A new round of cease-fire negotiations encompassing a variety of ethnic militias is slated to resume next week. "Our concern is that other [rebel] groups could be getting weapons from," Peng's rebel group, added Min Zaw Oo.
Htun Myat Lin, a spokesman for the rebels, said in a phone interview that his group had had "no contact" with Chinese authorities. He claimed the group now numbered 3,000. and in total the three allied rebel groups had 5,000 fighters.
Ranks have swelled in recent weeks, he said, particularly in wake of a Feb. 13 clash with government forces that left a number of civilians dead, angering the local populace.
The rebels, he said, want a federation-style arrangement with Myanmar's national government that grants Kokang a high degree of autonomy. "We don't want to be separate," he said.
Dai Yonghong, director of the Center for Myanmar Studies at Sichuan University, said China would not let the conflict near its border lead to serious degeneration of ties between the two governments -- particularly because the U.S., Japan and India all taking a new and heightened interest in Myanmar.
"Myanmar is China's security barrier and strategic buffer. China's top security concern is to keep Myanmar from joining the U.S. 'encirclement of China' policy," he wrote in a commentary last week for the East Asia Forum. "China needs to maintain good and sustainable bilateral relations with Myanmar to prevent this."