More than 60 firefighters responded to a fire at a recycling facility in St. Paul early Thursday.

An employee of the WestRock recycling facility in the St. Anthony Park neighborhood sustained minor smoke inhalation and was treated by paramedics at the scene, said Deputy Fire Chief Roy Mokosso.

The fire on Wabash Street, off Raymond Avenue, left “quite a bit of damage” to the roof and a mechanical room on top of the roof, Mokosso said. The fire set off the sprinkler system, which may have resulted in additional damage.

Firefighters responded about 12:10 a.m. Thursday and were at the scene for more than three hours.

The cause of the fire is under investigation. Preliminary information indicates it was accidental, either “some sort of mechanical or electrical fire,” Mokosso said.