An operator of several New Jersey TGI Fridays has been fined for serving customers cheap alcohol in place of the expensice liquor that they ordered.

Over 20 establishments (not all of them were Fridays) were found to be serving inadequate drinks to their customers. An undisclosed restaurant was serving rubbing alcohol with caramel color, to give it the appearance of whisky. Another filled alcohol bottles with water with a similar quality to what would be found in a river.

The Briad Group will pay the $5,000 fine, and wont contest the charges, USA Today reported.

Eight Briad-owned TGI Friday restaurants are under fire after "Operation Swill" conducted an investigation and seized over 250 bottles or liquor.

"At a very fundamental level, this is a very wrong practice," Michael Halfacre, director of the New Jersey Division of Alcoholic Beverage Control, said.

"Briad's restaurants were scamming customers by serving them a cheap substitute for what they ordered," acting New Jersey Attorney General John J. Hoffman said in a statement.

"This unlawful practice took advantage of consumers who were cheated out of what they thought they were purchasing. This fine should send a clear message to every bar and restaurant throughout New Jersey that customers should get what they pay for every time without exception," he said.

Detectives went into the restaurants and ordered their drinks "neat" so that no mixers or ice diluted the samples. They tested the drinks with a tool called a true spirit authenticator.

If the liquor tested negative for authenticity, it was sent to the manufacturer for further testing.

The eight Fridays will pay $400,000 for the violations, and an additional $100,000 to cover the cost of the investigation, ABC News reported.

Briad also faces another lawsuit by two women who claim they had a "uniform policy" to substitute the alcohol, which would be in violation of the New Jersey Consumer Fraud Act. The lawsuit seeks reimbursement of three times the amount of each fraudulent drink.

The establishments will employ a state-appointed inspector to keep an eye on their liquor-serving practices. If no more violations are found through June 2014, the restaurants will avoid a five day suspension of their liquor license.

Briad stated they were cooperating fully and looked "forward to putting the matter behind [them]," USA Today reported.

"In addition to the settlement, we have also made the operational adjustments, initiated new training programs and redoubled our efforts to ensure that all of our restaurants adhere to Fridays' extensive bar and beverage standards," the company said. "We believe that these actions will result in even higher customer satisfaction and a strengthened level of trust."

*This article has been edited to include corrections.

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