UPDATE: Tennessee authorities are seeking information from the public and law enforcement agencies that have reported cases of vehicles being shot on Interstate 81 in east Tennessee.

Tennessee's Department of Safety and Homeland Security and the Tennessee Highway Patrol are advising motorists to use extreme caution when driving on I-81 in Hamblen and Jefferson counties after vehicles were shot at on at least three different occasions.

1 - The THP says that on Friday, September 9 at about 10:50pm ET, a commercial vehicle was traveling north on I-81 near mile marker 17 when a small car passed. The commercial vehicle driver described seeing a bright flash inside the passing vehicle, and they believed it to be muzzle flash.  

THP responded to the location, however, neither the trooper nor the driver was able to locate a bullet hole.
2 - An armored vehicle was shot at Sunday, September 18 between 11:30pm and midnight. The occupants of an armored vehicle traveling north on I-81 heard a loud noise between the mile markers 4 and 20 and assumed a tire had blown.  

Once they reached their destination in a nearby state, the discovered a bullet impact on the passenger side of the cab.

3 - A car was shot Tuesday, September 27 at about 9:08pm. The bullet entered the front windshield of a vehicle, occupied by a family that was traveling north on I-81 at mile marker 10.5.
The driver noticed a silver Toyota Camry that passed their vehicle prior to the incident with only one headlight. THP does not know if that vehicle was involved.

Officials have not reported any injuries in the shootings, which took place this month.

Individuals and law enforcement agencies with pertinent information are asked to contact Sgt. Kevin Kimbrough at the highway patrol's criminal investigation division.

The Associated Press contributed to this report.