BATON ROUGE - Firefighters in Baton Rouge are determining what sparked an attic fire at a South Harrell's Ferry Road building. 

The Baton Rouge Fire Department said the Cypress Alley Office Park caught fire shortly before 8 p.m Sunday. 

Firefighters said no one was in the building when the fire started, and damage was contained to one-third of the building. 

No foul play is suspected, but investigators are still working to determine the cause of the fire.