POLK COUNTY, Fla. – A fatal two-vehicle crash that happened about 16 miles south of Mulberry on Wednesday morning remains under investigation by the Polk County Sheriff’s Office. The crash occurred around 8:00 a.m. Wednesday, deputies say. Both drivers were killed at the scene when a white 2021 Isuzu box truck collided with a white 1999 Peterbilt semi-truck with a dump trailer. Read: Police Vs. Teen: Memorial Day Swimming Pool Trespass In Lakeland Ends In Violence A fire that involved both vehicles spread to nearby grass and brush but was quickly extinguished. According to the preliminary inve…