An investigation found Riley committed 15 breaches of the Tennis Anti-Corruption Programme (TACP) between 2015 and 2020, and Kolar committed 25 breaches in the same time period.
The ITIA said Kolar and Riley collectively breached a series of TACP rules including contriving aspects of matches, wagering, facilitating wagering, courtsiding, conspiracy and failing to report corrupt approaches.
As of 14 March, both players are provisionally suspended and prohibited from competing in or attending any sanctioned tennis events organised or recognised by the governing bodies of the sport.
The decision on sanctions for both players will follow in due course.
The ITIA said the provisional suspension was granted under section G.4.a of the TACP 2023, which allows for a suspension if a player is found liable of one or more of the charges.