According to TMZ.com, rapper Nicki Minaj was punched in the mouth by a man believed to be her longtime boyfriend, Safaree Samuel. Minaj told police she was punched in the mouth during an altercation yesterday at a hotel in Dallas, Texas.

Minaj is in Dallas to perform a concert tonight at the American Airlines Center. She is currently on tour with Britney Spears.

TMZ has learned … Minaj was hanging out at the pool at the fancy Palomar Hotel when she got into a very intense verbal spat with an unidentified man she was staying with.

Nicki told a hotel employee to call police … while the man went to their hotel room. Nicki followed soon after.

When cops and paramedics arrived, Nicki told authorities their poolside fight continued inside of their room … and the man hit her in her lower lip.

Prior to socking Nicki in the mouth, Samuel tweeted this from his Twitter account:

Samuel left the scene before cops arrived, and like most domestic abuse victims, she is refusing to press charges against him.

Update: Samuel responds to the allegations that he attacked his girlfriend Nicki: