Two brothers who allegedly tried to extort $200,000 from jockey Gary Stevens are scheduled to appear in a Los Angeles courtroom Wednesday, authorities said.Mark Frankel, 25, of Sherman Oaks and his 29-year-old brother, Adam Frankel, of Encino were arrested and booked last month on suspicion of extortion and conspiracy. Although the case hasn't been filed with the Los Angeles District Attorney's office, investigators said the suspects' arraignment will occur Wednesday in an Inglewood courtroom.Authorities said that on Dec. 17 the siblings allegedly sent a note to Stevens' manager, who passed it along to the jockey after the seventh race at Santa Anita. When Stevens, 37, opened the envelope he found three photos and a message instructing him to pay $200,000, said Inglewood police Detective. Jeff Steinhoff.The snapshots -- reportedly taken from ABC television stills -- show Stevens moments after his 1995 Kentucky Derby victory aboard Thunder Gulch clasping hands with fellow jockey Pat Day, who rode Timber Country to a third place finish. "There were some accusations that Stevens had passed an electrical device to Day moments after the race, which were later found not to be true," Steinhoff said. "Mr. Stevens knew what these men wanted when he saw the pictures."The note asked that Stevens go to a phone booth near Santa Anita Park in Arcadia the next day and wait for further instruction. Police were monitoring the call.In that conversation, the caller believed to be one of the Frankel brothers demanded money from Stevens. The jockey asked for more proof from the caller of his alleged misconduct during the 1995 Kentucky Derby, Steinhoff said. A package was left at the same phone booth the following day, Tuesday, Dec. 19, with another note requesting another drop-off on Wednesday. Police were waiting for the Frankels on Wednesday when they picked up the bag planted by police that was filled with phony dollar bills, authorities said. Police then pursed the suspects on a high-speed chase. The fleeing motorist was hitting speeds of up to 120 m.p.h., Steinhoff said, and eventually lost the trailing police officers.The two men were arrested the next night, Thursday, Dec. 21. Authorities said Adam Frankel was armed with a small-caliber handgun when police arrived but was taken into custody without incident.Steinhoff said a third person may have been involved in the extortion scheme but no one has been arrested yet.Police are unsure why Stevens was targeted and don't believe the suspects knew the jockey. However, the suspects were familiar with the horse racing industry. Their father, Al Frankel, had been involved was part owner of a horse racing partnership, Steinhoff said.The Frankels are free on $35,000 bail. Attempts to reach them were unsuccessful.Meanwhile, Stevens continues his comeback march after retiring in December 1999. He told authorities he brought the note to their attention because of the recent death of friend, jockey Chris Antley, who was found dead in his Pasadena home last month. At the time of the Frankels' arrest, Inglewood police said there was no connection between Antley's death and the Stevens extortion scheme. Since that time, coroners have disclosed that Antley died from an accidental drug overdose.