WASHINGTON - The US Treasury announced on Monday that it has imposed sanctions on five Russian entities and three Russian individuals, accusing them of conducting "malicious cyber-enabled activities."

The blacklisted groups included Russia's Digital Security, Kvant Scientific Research Institute, Divetechnoservices and two other firms.

"The entities designated today have directly contributed to improving Russia's cyber and underwater capabilities through their work with the FSB (Russia's Federal Security Service) and therefore jeopardize the safety and security of the United States and our allies," said US Treasury Secretary Steven Mnuchin in a statement.

The punished Russian individuals were all related to Divetechnoservices, according to the statement.

In another statement, the Treasury designated six other individuals in Libya-related sanctions.

The sanctions will freeze any assets the individuals or entities punished hold in the United States and prohibit US citizens from conducting business with them.

The new move was the latest among a series of the Trump administration's actions against Russia's alleged "threatening" activities against the United States. It could be another blow on the already sinking ties between Washington and Moscow.

Earlier this month, Russian President Vladimir Putin signed into law a bill which allows him to respond to sanctions by the United States and other "unfriendly states."

Under the new law, foreign entities could be prohibited to provide services for Russia's central and local governments, conduct trade with Russian counterparts, or participate in the privatization of Russian property.

The US Treasury in April already banned 38 Russian individuals and entities, including seven business leaders and 17 senior officials, for their alleged "malign activity" around the world.