The US Treasury Department said its Office of Foreign Assets Control had frozen the assets of minister Alvaro Lopez Miera and the Special National Brigade (SNB), an office of Cuba's interior ministry, in relation to human rights abuses committed during a crackdown on protests on the island earlier in July.

"This is just the beginning -- the United States will continue to sanction individuals responsible for oppression of the Cuban people," Biden said in a statement shortly after the sanctions announcement was made.

Biden said his administration targeted Lopez Miera and the SNB -- a special forces unit nicknamed the Black Berets -- because they were "driving the crackdown" against protesters who took to the streets by the thousands in rare public anti-government demonstrations.

"As we hold the Cuban regime accountable, our support for the Cuban people is unwavering," Biden said.

He added that Washington was working closely with regional partners like the Organization of American States "to pressure the regime to immediately release wrongfully detained political prisoners, restore internet access and allow the Cuban people to enjoy their fundamental rights."

The sanctions freeze all of Lopez Miera's and the SNB's assets and interests in the United States, as well as prohibit any US citizen, resident or entity from engaging with them financially, according to the Treasury Department.

"Treasury will continue to enforce its Cuba-related sanctions, including those imposed today, to support the people of Cuba in their quest for democracy and relief from the Cuban regime," Treasury Secretary Janet Yellen said.

On July 11 and 12, thousands of Cubans took to the streets in 40 cities shouting "Freedom," "Down with the dictatorship," and "We're hungry."

One person has died and more than 100 have been arrested since the protests broke out over the worst economic crisis in decades.

According to the Treasury Department, Cuba's defense ministry and security services attacked people and "arrested or disappeared over 100 protesters in an attempt to suppress these protests."