State police Tuesday raided the three race tracks operated under a state-issued franchise by the New York Racing Association.
Raids were also carried out at Belmont and Aqueduct in Queens and at Saratoga Race Course 25 miles north of Albany.
NYRA President Terry Meyocks said police had search warrants when they arrived at the New York City tracks.
At the Saratoga track, which ended its season on Labor Day, police removed boxes of cashed betting tickets.
NYRA officials said they've been asked not to discuss the investigation and state officials aren't commenting.
NYRA is a private not-for-profit company formed in 1955 to run the three largest thoroughbred tracks in the state. It has a state franchise to manage the tracks through 2007.
The raid was conducted by the state Attorney General's Organized Crime Task Force, state police and the state Inspector General's Office.
"We have removed materials and we are analyzing them," said Darren Dopp, spokesman for Attorney General Eliot Spitzer. The suspected criminal activity may link the three tracks and NYRA officials are cooperating, Dopp said.
Meyocks said he was in his office at Belmont Park participating in a national teleconference at approximately 9 a.m. when the police arrived. He estimated that 30 police officers and investigators were at Belmont and said that some were still at the track Tuesday night.
A half-dozen state police arrived at the Saratoga Race Course, said George T. Hathaway, resident track facilities director. He said state police removed boxes of winning mutuel tickets.
"We save the cashed tickets until April 1 of the following year," he said.