The Chinese military is conducting live-fire drills on the border with Myanmar in what analysts say is a message that Beijing is losing patience with an out-of-control ethnic insurgency in the neighboring country. Over the past three months, bombs dropped by Myanmar’s warplanes on insurgents have strayed into China’s territory, provoking casualties, and thousands of Myanmar civilians have crossed into China's Yunnan province to escape the fighting.

"In addition to the bombing incidents, China has also been provoked by the intrusion over the Chinese border of a number of Myanmese," said Yue Gang, a military commentator and a retired military officer, who also said the exercise, which began early Tuesday, was clearly meant to push the Myanmar government to action over its failure to contain the conflict. "This is to show that Beijing is really unhappy about the issue," he said.

Chinese army spokesman Zhao Picong said the drills would take place in Gengma and Zhenkang counties in Yunnan, although it’s not yet clear when they will end. Xinhua, the official press agency, said an announcement would be made “in due course.”

A Chinese government official said the exercise was normal activity for the army, but also mentioned that Beijing had called on Myanmar to ensure the safety of the border.

There have been increased tensions in the border region since Myanmar government troops began battling insurgents in the northeastern state of Shan in February. A month later the fighting spread into China’s Yunnan province when five people were killed by a stray government bomb. In April two bombs injured five in China’s Zhenkang County.

As many as 90,000 civilians in northeastern Mynamar have fled the fighting, according to government officials quoted by Agence France Presse, which said that as many as 30,000 people, mostly from the ethnic Chinese Kokang group, had crossed over into Yunnan.

The Myanmar National Democratic Alliance Army (MNDAA), an insurgent group formed from the remnants of Chinese-backed guerrilla forces loyal to the defunct Communist Party of Burma, are the biggest rebel group in the region. A 20-year long ceasefire was broken in 2009 when government forces stormed the region of Kokang, one of the MNDAA's strongholds. However, it's yet to be seen whether a truce signed in Mar. 2015 between 16 armed ethnic groups and the armed forces of Myanmar will collapse because of the recent fighting.