Miami Beach police are investigating recent Grammy winner Chris Brown after an alleged robbery.

Christal Shane Spann, 24, claims that Brown stole her cellphone outside the Cameo Theater on Washington Avenue early Sunday morning.

According to the case report, Spann told Miami Beach police that she was inside the Cameo and saw Brown and a rapper known as Tyga exit the side of the club leading to Espanola Way.

Spann claimed Brown got into his Bentley and that she took a picture of him with her cellphone. Spann then claimed Brown grabbed her phone from her hands and said, "bitch you ain't going to put that on no website."

She said Brown then put up his car window and drove away. Spann flagged down a nearby officer, police said.

Besides releasing the case report, Miami Beach police would only say, "We have not charged Mr. Brown with anything.  This is an open investigation, and I cannot comment any further at the this time."

"My prosecutors are currently speaking with witnesses and reviewing all of the materials supplied by Miami Beach police," Miami-Dade State Attorney Katherine Fernandez Rundle said. "Only after these reviews have been completed would any type of action be considered or taken."

Just a week earlier, Brown won a Grammy Award in Los Angeles. But some critics said he was too well-received just a few years after pleading guilty to assault on his ex-girlfriend, Rihanna.