The Instagram and YouTube star, who goes by Ray Diaz on social media, has built a brand out of his workout videos and fitness advice.
The 33-year-old was arrested at about 5 a.m. on Friday in San Diego, with the assistance of the San Diego Police Department, according to the Los Angeles Police Department.
"The Los Angeles Police Department’s Robbery Homicide Division detectives have made an arrest in connection to a recent sexual assault incident," the LAPD said in a statement.
A day earlier, the police department had tweeted it was aware of a number of accusations against the Hollywood-native and was looking into them.
Several outlets have reported on Diaz's connection to videos published by DramaAlert, a site that reports on social media stars, allegedly showing the Instagram star verbally attacking a woman. Diaz responded to the allegations on Twitter on July 5, calling it "fake news."
Diaz has 3.1 million followers on Instagram, though his account is currently private. He has over 300,000 subscribers on YouTube.
He has parlayed his online success into several TV roles, including appearances on comedian George Lopez's TV Land show, "Lopez," and a starring role in the Zeus Network show, "Sober Coach." Zeus Network is a streaming platform specifically aimed at capitalizing on so-called social media "influencers."
He also worked as a trainer for FitPlan, an app that gives people a chance to work one-on-one with fitness trainers popular on social media. While still advertised in his Instagram bio, his page appears to be inactive. The company did not immediately respond to ABC News' request for comment.
Diaz's bail has been set at $500,000.