The U.S. Department of the Treasury Wednesday sanctioned several individuals and entities it says are supporting Hamas terrorist operations, including a Gaza-based exchange.

Among others, the sanctions targeted Buy Cash Money and Money Transfer Company, a company that the Treasury said had a long history of financing terrorist groups.

“The United States is taking swift and decisive action to target Hamas’s financiers and facilitators following its brutal and unconscionable massacre of Israeli civilians, including children,” said Secretary of the Treasury Janet Yellen in a statement.

Buy Cash , previously tied to wallets seized by Israel’s National Bureau for Counter Terrorist Financing in 2021, is accused of "having materially assisted, sponsored, or provided financial, material, or technological support for, or goods or services to or in support of, Hamas," according to the Treasury. The business included bitcoin among the assets in which it dealt.

The owner of the financial exchange, Ahmed M. M. Alaqad, was also sanctioned on Wednesday.

"This really shows how Treasury – how the U.S. – should go after any terrorist use of crypto," Yaya Fanusie, a former Central Intelligence Agency analyst who is head of anti-money laundering and cyber risk policy at the Crypto Council for Innovation, said in a CoinDesk TV interview on Wednesday. "It's pretty precise and targeted."

Blockchain analytics firm Elliptic said that while the U.S. sanctioned only one address associated with Buy Cash, it's aware of others used by the broker on multiple blockchains including Bitcoin.

"In total, our research has found that these addresses have received cryptocurrencies including Bitcoin and Tether worth more than $25 million since 2015," the firm said in a blog post.

UPDATE (October 18, 2023, 15:33 UTC): Updates with Elliptic analysis of Buy Cash activity.

UPDATE (October 18, 2023, 15:56 UTC): Updates with comment from Yaya Fanusie of CCI.