Traffic on Interstate 12 east and westbound near the Satsuma exit is congested after an 18-wheeler carrying other vehicles overturned, a Walker Police Department spokesman said.

It is unsure at this time what caused the automobile transport trailer to overturn, Walker Police Capt. John Sharp said.

Officers were already working an accident just west of Satsuma when the eastbound trailer overturned into the median, Sharp said. It is unsure if those two crashes were related.

Congestion is both eastbound and westbound, and Sharp said cars stopped in the area may have fallen off the trailer.

Check back later for more details.