Heavy fog is blamed for a massive multi car pile up in southeast Bexar County this morning, 1200 WOAI news reports.


  Deputies say more than thirty vehicles were involved in a series of chain reaction collisions on Interstate 37 between Hardy Road and Loop 1604.  Both northbound and southbound 37 had to be closed due to the wrecks.


  Deputies on the scene say visibility in the area is '100 feet or less,' and the wrecks are blamed on the inability of drivers to see the pile up developing ahead of them.


  There are no serious injuries, but the highway is expected to remain closed for some time.