New York’s attorney general isn’t happy with popular cryptocurrency exchange Kraken. The feeling is mutual.

The state’s legal chief said Tuesday that the San Francisco-based firm and two other digital-coin marketplaces may be operating illegally in New York. Kraken Chief Executive Officer Jesse Powell, known for his candid remarks on the internet, took to Twitter to express his displeasure.

Earlier this year, New York asked 13 major crypto exchanges for details on their operations, internal controls and safeguards against market manipulation and fraud. Nine of the platforms participated, while the other four, including Kraken, claimed they don’t allow trading in the state. Attorney General Barbara Underwood said in a report Tuesday that her office referred Kraken, Binance and Gate.io to the New York Department of Financial Services for possible violation of digital-currency regulations.

Kraken has said that it stopped operating in New York after the state in 2015 created the “BitLicense” -- a special permit that applies to virtual-currency exchanges -- which has drawn criticism from crypto companies for being too burdensome. In April, Powell called the state’s inquiry “insulting.’’ The next month, he said in an interview that the attorney general doesn’t have authority over Kraken.

“The Kraken platform’s public response is alarming,” Underwood’s report said. “In announcing the company’s decision not to participate in the Initiative, Kraken declared that market manipulation ‘doesn’t matter to most crypto traders,’ even while admitting that ‘scams are rampant’ in the industry.”

This article provided by Bloomberg News.