(CNN) - Sources familiar with the investigation tell CNN investigators have identified at least eight instances in which Eliot Spitzer used the Emperors Club VIP over the past several years but are still examining the records to see if there are more.
They say Spitzer began using Emperors Club VIP about eight months ago.
A criminal investigation began when North Fork Bank notified the U.S. Treasury Department about suspicious activity regarding his bank accounts, the sources said. The suspicious activity involved the transfer of money to shell companies identified as having links to the prostitution ring, they said.
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–CNN's Kelli Arena