With just limited access to the site, firefighters have no choice but to let the blaze burn out on its own.

GALENA, Ill. — A BNSF Railway freight train loaded with crude oil derailed Thursday near the northern Illinois city of Galena and erupted into flames, authorities said.

The train derailed around 1:20 p.m. in a rural area where the Galena River meets the Mississippi, said Jo Daviess County Sheriff’s Sgt. Mike Moser. The blaze didn’t prompt any evacuations.

“There’s no structures and no houses in that area,” Moser said.

Galena City Administrator Mark Moran told the Dubuque Telegraph Herald newspaper in Iowa that eight tankers had left the track. “Two of those were still upright. The other six were not,” she said.

The train had 103 cars loaded with crude oil, along with two buffer cars loaded with sand. A cause hadn’t been determined.

Firefighters could only access the derailment site by a bike path, said Galena Assistant Fire Chief Bob Conley. They had to pull back for safety reasons and were allowing the fire to burn out.

The derailment comes amid increased public concern about the safety of shipping crude by train. Since 2008, derailments of oil trains in the U.S. and Canada have seen 70,000-gallon tank cars break open and ignite on multiple occasions, resulting in huge fires. A train carrying crude from North Dakota crashed in a Quebec town in 2013, killing 47 people. Last month, a train carrying 3 million gallons of crude derailed in West Virginia, leaking oil into a river and forcing hundreds of families to evacuate the area.