G-Unit member Tony Yayo is reportedly back in prison, for violating terms of his probation.According to sources, he must serve 90 days in prison for traveling to Las Vegas with his G-Unit crew.Other sources refuted the notion that the violation was a result of traveling outside of New York.Interscope representative’s declined to comment on the situation.The rapper was released from Lakeview Shock Incarceration Correctional Facility in New York on January 9 after serving a year for gun possession.The rapper was arrested New Year’s Eve of 2002 because of a previously existing warrant.Despite the outstanding charges, the rapper had been continuously promoting the G-Unit through mixtapes, DVDs and music videos.