ATLANTA — Rapper Gucci Mane has pleaded not guilty to an assault charge stemming from an altercation with a fan at a downtown Atlanta nightclub.

The rapper, whose real name is Radric Davis, was charged with aggravated assault with a weapon. An arrest warrant was issued for Gucci Mane after James Lettley of Fort Hood, Texas, who serves in the military, told police the rapper struck him in the V.I.P. area at Harlem Nights Club on March 16.

Lettley said he was in Atlanta for his birthday and hoped to get a picture with the rapper when he was attacked.