A crash involving an overturned tractor-trailer has shut down several lanes on Interstate 77 north of uptown Charlotte Friday morning. According to the Charlotte Fire Department, the wreck happened on I-77 northbound at Exit 11 near West Brookshire Freeway around 8 a.m. The North Carolina Department of Transportation said the wreck is blocking three lanes on the interstate. It is unclear what caused the wreck. Firefighters did not say whether anyone was injured.