Two factories in the Myanmar city of Yangon run by Fast Retailing Co.'s local partner were set ablaze on the weekend, the operator of the fast-fashion Uniqlo and GU brands said Tuesday.

The extent of the damage caused at the plants Sunday amid protests against a Feb. 1 military coup remains unknown, the company said, adding it is confirming the situation in regard the fires.

On Sunday, Chinese-linked factories in Yangon were attacked, leaving many people injured, according to the Chinese Embassy in Myanmar.

The Yangon factories of Fast Retailing's partner are located in townships where martial law has been declared, the company said, adding no injuries related to the fires have been reported as the plants were closed on Sunday.

There were five clothes production plants operated by Fast Retailing's partner company in Yangon and one in Bago, northeast of Yangon, as of March last year, according to the company.

Many apparel companies and related corporations from Japan operate in the townships in Yangon currently under a declaration of martial law, according to sources familiar with the businesses.

Japanese engineers employed by apparel companies from China and South Korea are also working in the townships.

Martial law was declared in Hlaingthaya and the neighboring township of Shwepyithar on Sunday, the first such declarations in Yangon since the Feb. 1 military coup, followed by orders in four more townships in the city on Monday.

The declaration gives the military administrative and judicial authority in the areas.

On Sunday, at least 38 people were killed by security forces during protests, a Southeast Asia-based human rights organization said.

The Assistance Association for Political Prisoners said the death toll equaled the number killed on March 3, the bloodiest day since the Feb. 1 military coup.

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