The U.S.-designated terrorist group Hamas has raised bitcoin donations through the largest U.S. crypto exchange, according to an Israeli blockchain intelligence startup Whitestream.

The Israeli financial news site Globes reported on Sunday that Hamas, which controls Gaza, has begun funneling funds through Coinbase.

For the first time, a bitcoin address was publicized for Hamas on Thursday through the cloud-based instant-messaging service Telegram. It was discovered by entrepreneurs Itsik Levy and Uri Bornstein, who “succeeded in decoding the bitcoin transfers on the Hamas address and detecting the Palestinian organization’s actions through the digital wallet of US. company Coinbase. Whitestream’s findings were forwarded to the security agencies,” reported Globes.

On Saturday, the same Telegram channel publicized a second bitcoin address that allowed Hamas to accept donations, though it was through a digital wallet apparently not linked to Coinbase. In addition to Coinbase, the second address has so far received funds from the American trading platform Bittrex.

The two bitcoin donation addresses totaled $2,500, according to Levy.

According to Globes:

Whitestream discovered that one of the bitcoin donations transferred to Hamas’s Coinbase wallet was sent on Thursday from a ‘Buy Cash’ bitcoin trader in Khan Yunis in the Gaza Strip. Other bitcoin donations were sent to the Palestinian organization from wallets connected to Chinese cryptocurrencies exchange Binance and Russian cryptocurrencies exchange Vilkov, and from a wallet of another Coinbase account. Whitestream’s check also revealed that bitcoin donations were sent late last week from Hamas’s coinbase wallet to two bitcoin wallets: one belonging to CoinPayments, a company registered in the Cayman Islands, and one belonging to Binance.

“In exposing illegal activity, you could say that blockchain itself does most of the work. All activity on the network is registered and documented, so it can be read at a later stage,” Levy told the outlet a couple weeks ago. “We have been decoding blockchain transactions for a long time. According to our figures, only 2 percent of total bitcoin turnover involves the darknet or is related to terrorist or criminal activity.”

It is currently unknown if Coinbase has taken action against Hamas for using its exchange.