Eighteen and counting. That is how many vehicles have been damaged by rocks or objects thrown off overpasses on I-40 mainly in Roane and one in Cumberland County. Yesterday, two more motorists contacted the Tennessee Highway Patrol to report damage done. Earlier this week, an incident took place at the 336 mile marker overpass in Cumberland County. So far, law enforcement has no suspects. No one has been hurt yet in these incidents. If you see any suspicious activity on the overpasses, contact 911 immediately.