The Covington Fire Department received the call about 3 p.m. today for a fire alarm, which was changed to a structure fire call after plant personnel checked out the source of the automatic alarm.

When firefighters arrived on the scene, they saw smoke rising from the dust filtration system, housed in the back of the plant, said CFD Deputy Chief David Gunter.

Contractors had worked on the system earlier in the morning, according to Gunter.

"After they repaired all the repairs, they left and the fire broke out," he said.

The sprinkler system was automatically activated and a call sent out to dispatchers. The plant, which employs less than 100 people, was evacuated.

The filtration system had been moved to the outside of the building about eight years ago to help prevent fire incidents and this was the first dust-related fire since the move, said CFD Assistant Fire Marshal Tony Smith.

Shortly before the call from Smurfit-Stone, CFD units had also put out a small grassfire next door at Pactiv, which had started due to utility issues, said Smith.