State regulators fined the Sioux City Belle riverboat/casino 10-thousand dollars today for allowing an underage gambler on the boat. The State Racing and Gaming Commission says an 18-year-old woman entered the boat on February 10th and gambled for about an hour before being discovered. Gamblers at state-run casinos must be at least 21. It is the boat’s second fine for underage gambling. Casino general manager John Pavone apologized to the commission, and said they’ve taken steps to re-train security personnel. He says they’ve been working hard to keep underage gamblers out.Pavone says the girl is part of a growing trend brought on by a nearby Native American casino. The Native American casino lets anyone 18 or over gamble, and Pavone says teens mistakenly think they can also gamble at other casinos. He says the number of underage gamblers they’ve turned away has tripled since the Native American casino opened.