The eastbound lanes of the Indiana Toll Road are closed at the mile marker 24 toll booth after a semi caught fire and the flames spread to the toll booth.

Firefighters were called to the toll booth fire just before 7 a.m. and battled flames for at least an hour, according to the Indiana State Police.

Traffic backed up for several miles in both directions because the fire blocked all lanes. Vehicles have been diverted off the Indiana Toll Road at exit 23 and exit 31.

Westbound lanes were reopened by 10:30 a.m. EST (9:30 a.m. CST) and at least three eastbound lanes are expected to open at 10:45 a.m. EST (9:45 a.m. CST), Indiana State Police said.

The semi that caught fire was driven by a 67-year-old New Jersey man who was not believed to have been injured. The semi was hauling potatoes and apples. It’s not clear why or how the semi caught fire.

The fire remains under investigation.