The US Government has started a new crack down on online poker, freezing accounts that handle the winnings of thousands of players.

The Poker Players Alliance says that the US Attorney for the South District of New York instructed three banks to freeze accounts that held $30 million. Internet gambling has always been illegal in the United States, however online poker companies have claimed that the law doesn’t apply to poker due to poker being a game of skill, as opposed to other types of gambling.

Copies of the orders, obtained by AP state that banks should treat the frozen accounts “as legally seized” by the FBI. The letters claims that the government has probable cause that the gambling payments of U.S. residents had been directed to offshore illegal Internet gambling businesses, and state that the accounts “constitute property involved in money laundering transactions and illegal gambling offenses.”

It’s not known at this stage which poker sites are affected.