The US Treasury Department in a statement said it blacklisted Myanma Timber Enterprise and Myanmar Pearl Enterprise, adding that the pearl and timber industries are economic resources for the Myanmar military.

“Today’s action demonstrates the US’ commitment to targeting this specific funding channel and promoting accountability for those responsible for the coup and ongoing violence,” Andrea Gacki, director of Treasury’s Office of Foreign Assets Control, said in the statement.

The Southeast Asian country has been in crisis since the February coup when the military seized power from Aung San Suu Kyi’s elected government, with almost daily protests and a crackdown by the junta in which hundreds of people have been killed.

The Assistance Association for Political Prisoners (AAPP), an activist group, says 738 people have been killed by Myanmar’s security forces since the coup and 3,300 people are in detention. Another 20 people have been sentenced to death and are in hiding.

Washington has responded by targeting the revenue of the military through several rounds of sanctions.

Wednesday’s action freezes any US assets of the businesses and generally bars Americans from dealing with the companies that the Treasury said are responsible for timber and pearl exports from Myanmar.

The Environmental Investigation Agency, a nonprofit that documents timber industry abuses in Myanmar and elsewhere, said this month the military junta now profits from the export of teak through Myanma Timber Enterprise.

That teak is sometimes exported to the US and Europe and used for luxury furniture and for the decks of high-end yachts, the group says.