Fire investigators are trying to figure out what touched off a large warehouse fire at North Foster and Choctaw on Wednesday night.

Burning rubber stored inside the warehouse sent thick plumes of heavy black smoke throughout the area after the fire broke out around 9:30 p.m. in the Capitol Steel warehouse at 2655 N. Foster Drive.

Dozens of firefighters and 10 trucks battled the flames well past midnight, bringing the fire under control by 12:20 a.m. Thursday, said Mark Miles, a Fire Department spokesman.

Cleanup work continued at the warehouse late Thursday morning.

The business was closed at the time of the fire and no one was inside the warehouse, Miles said. No firefighters were hurt.

The first firefighters arriving at the warehouse found the building engulfed in flames, Miles said, and quickly called for backup.

Curt Monte, another Fire Department spokesman, said the warehouse owner told him Thursday that some of the rubber materials stored at the warehouse are salvageable despite the fire.

Monte said the steel-framed building appears structurally sound.