Firefighters say when they arrived this morning, flames were shooting out of the abandoned building. Then part of the roof collapsed and a floor caved in.
Right now, authorities are calling the fire suspicious and are speaking with someone who was scene near the fire when it started.
Some heavy equipment had to be hauled in to tear the building down to make sure the fire is completely out. The old warehouse is known to be a hang out for some of Rockford's homeless. The building is a total loss, fire investigators say that's a loss of about 100,000 dollars.