A midday mess on Interstate 77 is being cleared, but traffic remains slow on both sides of the highway in south Charlotte.On the northbound side, a car fire late this morning caused the problem. On the southbound side, a wreck caused the problems. Both problems are south of the uptown area.Authorities report a Mazda caught on fire on northbound I-77 near the Remount Road exit. All occupants escaped the car safely, but traffic was badly snarled for about a half-hour. Police were able to reopen two of the northbound lanes by 12:45 p.m., and traffic is moving again.But backups will continue until about 1:30 p.m., as crews remove the burned vehicle.On the southbound side, the wreck happened near the Arrowood Road exit.Reportedly, a trailer being pulled by a truck came loose, went off the right side of the road, and overturned. Traffic is getting past the scene, but there are backups.