State regulators in the US state of Pennsylvania say a gambler won a US$25,000 jackpot on a Pittsburgh casino poker machine that should have paid out only US$12.

The Gaming Control Board told the Pittsburgh Post-Gazette the false jackpot happened on May 29, 2010.

It was one of five at Rivers Casino involving machines that were not properly tested or certified.

The board was to have levied an unspecified fine against the casino but it vetoed a consent agreement with the casino on Monday after some board members felt a stronger message needed to be sent.

Casino officials say the player was allowed to keep the jackpot and that it paid all taxes on it.

Rivers spokesman Jack Horner says the casino takes the matter seriously and has retrained all of its technicians.