Fulton County Sheriff's Office

Rapper Rod Wave was arrested in Fulton County, Georgia Friday on weapon and drug charges.

TMZ has learned he was arrested by the Atlanta Police Department for possession of a firearm or knife during the commission of or attempt to commit certain felonies, reckless driving, possession of a Schedule V controlled substance and possession of Schedule II controlled substance.

He is still in custody as of Saturday morning, but won't be for long. Rod's attorney, Drew Findling , tells TMZ ... he already had his first appearance in court, where they agreed to an $8,000 bond.

It is unclear what led to the "Leavin" hitmaker's arrest. TMZ has reached out to the APD for more information ... so far, no word back.

Rod -- born Rodarius Green -- found himself behin

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