RENO, Nev. (AP) _ Harrah's sports book said Wednesday it is refunding outstanding bets on the Olympic 100-meter race, in which Ben Johnson was disqualified for steroid use, but other Nevada books honored similar wagers.

The Canadian top finisher was stripped of his gold medal, which was given to Carl Lewis of the United States, who finished second.

''It didn't seem fair to pay with Johnson as the winner because he cheated,'' said Joe Bachman, manager of Harrah's Reno sports book. ''But Carl Lewis didn't win the race either. If Ben Johnson wasn't in the race, who's to say what would have happened.''

Mike Rumbolz, chairman of Nevada's Gaming Control Board which enforces betting laws, said it is up to each sports book whether to pay off on disqualified winners.

Several Nevada bookmakers said the Olympic results should be treated like a horse race in which bettors are paid off for winners later disqualified.

''In horse racing, when a race is run and the results are declared official at the finish line, that's that. Bettors are paid off no matter what happens later,'' said Scott Hall, assistant manager of the Reno Turf Club.

The Turf Club did not put out a line on the Olympic matchup. The Hilton and the Aladdin hotel-casinos and Little Caesars sports books in Las Vegas joined Harrah's in taking bets on the Friday race, and all three paid off on Johnson, as did books in London.

''We paid off on Johnson because, let me ask you, 'who won the race?,''' said Gene Mayday, manager of Little Caesars. ''Johnson did. We didn't ask whether he took drugs or not. It doesn't matter. He crossed the finish line first.''

''For betting purposes, Johnson was the winner, is the winner and will be the winner,'' agreed Art Manteris, director of the Las Vegas Hilton sports book.

Bachman said less than $10,000 was bet on the two men at Harrah's with most of the money on Lewis at 5 to 6 odds. The line on Johnson was 11 to 10 and was 3 to 1 on any one else in the 100-meter race.

Odds of 5 to 6 would pay off $5 for each $6 bet, plus the amount of the wager.

Half of the Johnson bettors were paid off before Harrah's decided on the refund, but Bachman would not say how much money that involved.

''We just lost in the deal because we paid off some bets and then we had to refund, too,'' he said.

In the future, Harrah's probably will inform bettors at the window that the winner at the finish line will be paid off, Bachman said.