UPDATE (WKOW) -- The Madison Fire Department says it is classifying the fire at All Metals Recycling as accidental with an undetermined ignition source.
Investigators think the fire and explosion may have happened as a result of either the failure of a compressed gas cylinder or an unintentional release of compressed gas.
Investigators are still trying to identify the specific ignition source. The fire department says it cannot rule out heat in the form of friction from a grapple crane being operated at the time of the fire.
UPDATE (WKOW) -- Madison firefighters are packing up and leaving the scene of a massive fire on the city's south side as of 5:00 a.m.Thursday.
They had stayed through the night to make sure no hot spots sparked the fire again. 27 News sent a crew to the scene this morning to talk with firefighters, who said the scene looked secure and investigators would be out again Thursday morning to follow up.
UPDATE (WKOW) -- Madison fire officials are reporting they have contained a fire that started in a pile of cars and car parts at the All Metals Recycling facility, located in the 1800 block of South Park St.
Chief Steve Davis says the pile is about 30 feet tall and 30 feet across. Firefighters at the scene tell 27 News they will likely stick around until 6:00 a.m. Thursday to monitor the smoldering hot spots.
Firefighters used a crane to pull out pieces of car parts so they could access these hot spots. They are still trying to figure out what started the fire.
UPDATE (WKOW) -- Madison Fire Chief Steven Davis says the fire started in a pile of cars and car parts that is about two stories tall and about 30 to 40 feet wide.
Davis says crews are using a crane to pull out cars one by one to thin out the mess.
He says so far, the fire has not spread to any buildings.
Davis says his agency is rotating firefighters to make sure they do not get fatigued.
At this point, there is no word on what caused the fire. No one has been hurt.
MADISON (WKOW) --- Madison Fire officials are headed to South Park Street near Wingra Drive in Madison for reports of an explosion and fire. Fire officials ask people to avoid the area on your commute home as traffic is backed up already.
Officials tell 27 News they are on the scene of the fire at All Metals Recycling at 1802 South Park Street.
Company spokesperson says that all employees are accounted for and there are no injuries.
We will continue to update you here as we learn more.