An Atlantic City casino that called off a high-stakes poker tournament last month because a player introduced fraudulent chips is facing a class-action suit from other participants, who claim their steep entry fees and expenses weren’t reimbursed.

The suit, filed in New Jersey state court on behalf of more than 4,000 people who bought into the “Big Stack No-Limit Hold ’em” event at the Borgata Hotel Casino and Spa, charges the casino negligently supervised the event.