No public agency may authorize, provide for or make any payment to any vendor or contractor upon any contract in violation of Section 4. It shall be a business offense for any vendor or contractor to knowingly enter into any contract in violation of Section 4 or to knowingly violate contract provisions required by Section 4. Each such violation shall subject the violator to a fine of the greater of $5,000 or the payment price received by him as a result of such violation. The Attorney General is authorized to file and prosecute a complaint in the circuit court of any county in which the contract was in whole or in part executed or performed.