One of the Island Boys tried passing himself off as his twin brother during his reckless driving arrest a few weeks ago ... so claim the cops anyway, who got it all spelled out in a report.
According to new legal docs, obtained by TMZ Hip Hop, officers say they observed Franky Venegas driving at a high rate of speed in his yellow Corvette Stingray on May 24 out in Fort Lauderdale, FL.
Cops claim that after witnessing Venegas speed into a parking lot, they got a call about the yellow Corvette and another gray vehicle near multiple people armed with guns.
Officers say they put their emergency lights on and swarmed in ... making contact with Venegas -- who they say identified himself as "Alex." Of course, Alex is Frank's twin bro ... and the other half of the Island Boys.
Cops say a quick background check determined this info was false and they later located his state ID, confirming him to be Franky, AKA Kodiyakredd.
Cops say the background check also revealed Venegas was driving without a valid driver's license, so he was arrested and hauled off to the Broward County Jail on the spot and booked for driving without a valid license, giving a false ID, and reckless driving.
He was subsequently released on May 25.