Two dozen people cheated casinos in Mississippi, several states and Canada out of at least $3.3 million over five years by using technology and bribes to rig card games, federal prosecutors alleged in indictments unsealed Thursday.

Members of the organization would signal a dealer to do a false shuffle and bet on the known order of the cards, the indictments state. Grand jurors also alleged that the ring used hidden transmitters and special software to predict the order in which cards would appear.

In all, three indictments were unsealed Thursday — two in Seattle and one in San Diego — naming 24 defendants in an alleged racketeering enterprise dating from March 2002. The so-called Tran Organization was allegedly based in San Diego.

Seven of 19 named in the San Diego indictment also were indicted in Seattle. Jacob Dyson Nickels, the son of Seattle Mayor Greg Nickels, was among five other men charged there.

The scheme netted $3.3 million from U.S. casinos, according to the indictment. However, interim U.S. Attorney Karen Hewitt in San Diego said the actual losses could be much higher. The losses included $868,000 won in 90 minutes in October 2005 at the Resorts East Chicago hotel and casino in East Chicago, Ind.

Casinos in Ontario, Canada, may have lost nearly $2 million, said Rob Knudsen, director of the gaming enforcement branch of the Ontario Provincial Police.

“We are not aware of any other cases of this magnitude,” said Kathy Leodler, acting head of the San Diego FBI field office.

Authorities said the scheme targeted 18 gaming parlors in Canada, Mississippi, California, Nevada, Louisiana, Washington state, Indiana and Connecticut. Ten casinos were owned by American Indian tribes.

The scheme involved bribes to casino supervisors and dealers during blackjack and mini baccarat and use of blocks of unshuffled cards, prosecutors contend.

The first indictment in Seattle was returned under seal in February 2006 and alleged a scheme to steal more than $1 million from the Emerald Queen Casino near Fife, Wash. The second, returned under seal in March, added Nickels, 25, who is charged with one count of conspiracy and four counts of theft of funds from a gaming establishment on Indian lands.

He was a pit boss at the Nooksack Indian Tribe’s Nooksack River Casino in Whatcom County in the summer of 2005 when he accepted $5,000 to introduce one of the ring’s conspirators to crooked dealers, according to the court document. Two of his co-defendants won more than $90,000 on mini baccarat that October, the indictment states.

Mayor Nickels said Thursday he and his wife had just learned of the charges against their son.

“We will be encouraging him to cooperate fully with the investigation. Until we know more we will have no comment on the substance of these allegations,” Nickels said in prepared remarks.

It was not clear whether any of the defendants had attorneys.

The charges in San Diego range from conspiracy to money laundering to theft from an Indian casino. Conspiracy carries a maximum penalty of 5 years in prison; theft of funds from Indian casinos carries a maximum 10 years.

Thirteen other people also were arrested in the same sweep in Ontario and were expected to face charges there, said Knudsen of the Ontario Provincial Police.