UPDATE (5 p.m.):

The fire involved an 18-wheeler carrying gallons of milk, according to the Hamilton County Office of Emergency Management (HCOEM).

The Tri-Community Volunteer Fire Department, Bradley County Fire Rescue and the Hamilton County Hazmat team responded to the scene.

Officials estimate about 5,000 gallons of milk spilled and mixed with diesel from saddle tanks.

No injuries were reported.

HCOEM says the Hazmat team used pads and boom to contain the milk from entering storm drains.

EARLIER:

A tractor-trailer caught on fire on Interstate 75 South Saturday afternoon, Tennessee Highway Patrol says.

The fire happened near mile marker 16, according to THP.

They warn anyone traveling in and around Hamilton County to expect significant traffic.

Both travel lanes are currently open.

THP says crews are working to clean up the area, and that drivers should proceed with caution.

We are working to learn more about the cause of the fire.

Depend on us to keep you posted.