DES MOINES, Iowa — A fire on a bike trail bridge over the Raccoon River in Adel early Monday morning caused significant damage.

The Dallas County Sheriff’s Office said it was notified about a bridge fire on the east side of Adel around 2:01 a.m. The bridge is part of the Raccoon River Valley Bike Trail.

Because of the location and terrain around the bridge, firefighters faced challenges in accessing it. A portion of Highway 6 was temporarily closed during firefighting efforts.

The DCSO said the bridge suffered significant damage and is unsafe for use. The section of the trail that the bridge is part of was already closed because of scheduled maintenance and improvements.

Officials are continuing to investigate the cause of the fire.

Fire crews from Adel, Dallas Center, De Soto, Redfield, Minburn, Van Meter, and Waukee all assisted in putting out the fire.