From UFC website
The UFC organization was notified today that the U.S. Anti-Doping Agency (USADA) has informed Jon Jones of a potential Anti-Doping Policy violation stemming from an in-competition sample collected following his weigh-in on July 28, 2017.
USADA, the independent administrator of the UFC Anti-Doping Policy, will handle the results management and appropriate adjudication of this case involving Jones, as it relates to the UFC Anti-Doping Policy and future UFC participation. Under the UFC Anti-Doping Policy, there is a full and fair legal process that is afforded to all athletes before any sanctions are imposed. The California State Athletic Commission (CSAC) also retains jurisdiction over this matter as the sample collection was performed the day before Jones’ bout at UFC 214 in Anaheim, CA, and USADA will work to ensure that the CSAC has the necessary information to determine its proper judgment of Jones’ potential anti-doping violation.
Additional information will be provided at the appropriate time as the process moves forward.
Jon Jones has tested positive for steroids in his UFC 214 victory over Daniel Cormier, and he has been stripped of his title ... TMZ Sports has learned.
Our sources tell us ... Jones tested positive for Turinabol -- an anabolic steroid.
Jones won the July 29 fight -- taking the UFC light heavyweight belt from Cormier with a savage head kick followed by a barrage of punishing punches to Cormier's head.
The title now goes back to Cormier.
It's the second time Jones has failed a USADA drug test. He tested positive for banned substances in 2016 before UFC 200 and was pulled from the main event. Jones got socked with a 1 year ban.
We're told this time around, he could be banned for up to 4 years.
Jones had blamed his previous failed test on a male enhancement pill. He claimed he didn't realize the pill contained a banned substance and insisted he was NOT trying to gain a competitive edge.
If the test results hold up, it's unclear how he'll explain his way out of this one.