Chinese factories torched as mainland workers hunker down under martial law -- Beijing is being pulled into the ulcerous crisis in Myanmar, an unravelling country it had carefully stitched into its big plans for Asia.

During a January 2020 visit to Myanmar, Chinese President Xi Jinping elevated the Southeast Asian neighbour to "country of shared destiny" status, Beijing's highest diplomatic stripe.

The aim was to nudge Myanmar decisively towards China -- and away from the United States -- and drive through projects worth billions of dollars under the Belt and Road Initiative, including an oil and gas pipeline and a port to the Indian Ocean.

Fast-forward one year, and the strategically located country has tipped into bloody chaos after a coup took out Aung San Suu Kyi's government.

The massive pro-democracy movement which has since unfurled accuses China of waving through the generals' power grab and trading Myanmar's freedom for its own strategic gain.

As Myanmar security forces kill protesters -- more than 200 so far -- Beijing faces a dilemma: back the men with guns or side with an increasingly anti-China public.

"China doesn't really care who is in government, but it wants a government that will protect Chinese projects and interests," said Richard Horsey, a Myanmar political analyst.

But "this is a military that Beijing doesn't think can bring stability... and the more China tries to build a relationship with that regime, the more the public will be put offside."

That is laden with danger for Chinese interests. At least 32 China-owned textile factories were burned down in several Yangon townships on Sunday, according to Chinese state media, causing around $37 million in damage.

A foreign ministry spokesman in Beijing demanded the immediate protection of "Chinese institutions and personnel".

Chinese businesses were closed Tuesday in the flashpoint areas, leaving workers holed up in a "hostile environment" cloaked by martial law, according to a representative of a garment factory in Yangon's Shwepyitar township.

Ominous commentaries have since seeped out of Chinese media with one saying Beijing could be prodded "into taking more drastic action... if the authorities cannot deliver and the chaos continues".

Twitter accounts of Myanmar pro-democracy groups allege -- without offering clear proof -- that the army carried out the factory attacks to justify a crackdown in which dozens of protesters died.

Ripples of anti-China sentiment in Myanmar could become waves across a Southeast Asian region suspicious of China's reach, influence and penchant for debt-trap diplomacy to get BRI projects over the line.

"Any broad-based popular uprising against Chinese interests can be contagious and percolate anti-China grievances through Cambodia, Laos and elsewhere," said Thitinan Pongsudhirak, a professor of political science at Thailand's Chulalongkorn University.

"China had figured out this piece (Myanmar) of its geostrategic puzzle," but now there is "no easy play ahead".