Frankfort, NY (WIBX) - We now know what caused Wednesday's massive fire at the former Union Tools site in Frankfort.

Frankfort fire officials say two workers stripping materials inside one of the buildings sparked the fire.

The buildings were being prepared for demolition, with workers removing windows and asbestos.

No one had been using the site since Ames True Temper left in 2006.

Fire crews from four counties battled the fire.