LINCOLN -- Lincoln Firefighters battled a fire Friday morning inside the Sapp Brothers Petrolium warehouse at 5901 Cornhusker. Fire units were called about 4am and gained control of the fire within 15 minutes after arrival. Employees came to work, heard fire alarms sounding and the sprinklers going off with smoke in the building. A fire apparently started in a semi-truck in the warehouse area and the sprinklers kept it contained. HazMat crews were called, too, because of fuel and other chemicals on the property. Multiple types of oils, lubricants, methanol and racing fuel are stored in the warehouse. There's a pit in the warehouse that is used to trap any chemicals that spill and water filled it up, causing the oil to overflow. Batallion Chief Tim Linke tells KFOR News some of the overflow only made it out to the parking lot. The semi-truck where the fire originated is a total loss and smoke damage was reported in the warehouse. The cause of the fire is still under investigation.