Fivio Foreign is in police custody after getting busted with a gun with the serial number scrubbed off.

Last night, the drill rapper left his 2018 Mercedes running outside a Fort Lee, New Jersey Citibank.

Sgt. Howard Ginsburg approached Fivio and asked for his license.  Instead of complying, he fled on foot toward a luxury apartment building.

While Ginsburg stayed by his police car, his partner Sgt. Gabriel Avella chased Fivio on foot.  During the pursuit, a handgun fell out of Fivio's waistband.

The serial number on the .25 caliber weapon was scrubbed off.  When Avella caught him, he required backup to get Fivio in cuffs.

Fivio was charged with weapons possession, having a defaced firearm and resisting arrest,  while Avella was transported to a local hospital for a minor wound.

The rapper is scheduled to see a judge today.