BOISE, Idaho (AP) _ A sheriff has been indicted on charges of racketeering and operating a gambling business after three businessmen admitted bribing him and relying on his deputies to warn them of police visits, authorities said.

A four-count indictment handed down Thursday accuses Shoshone County Sheriff Frank Crnkovich (pronounced sink'-o-vich) of accepting or soliciting $12,000 in bribes from brothel madams, video poker game owners and others.

He could face 20 years in prison if convicted of all four felony counts. He's scheduled to appear in federal court March 23. Federal officials wouldn't say whether he would be arrested.

Crnkovich didn't return calls to his office Friday.

The charges were corroborated by guilty pleas from three businessmen who admitted paying Crnkovich cash bribes and conspiring with him to run a gambling scheme, authorities said.

The indictment alleges Crnkovich protected bar owners from gambling and liquor crackdowns by using his deputies to watch for and report on visits to county by officers from other agencies.

A grand jury inquiry into gambling, prostitution and drug activities in the northern Idaho county started after 150 federal agents raided 58 Silver Valley bars June 23.

The indictment, which includes an obstruction of justice charge, says that on the morning of the raid, Crnkovich met with an owner of video poker machines, apparently to tip him off about the raid.

Federal prosecutors wouldn't say whether they expect any further indictments.