The Wooonsocket Fire Marshal's office reports the cause of an Oct. 3 fire that heavily damaged an optometrist's office under construction at 385 Mendon Road was oily rags left overnight.

The rags, left in a pile in a box in a doorway by a painter who was varnishing doors in the building, caught fire via spontaneous combustion, according to Fire Lt. David Degrane. 

The call for the fire came in at 12:45 a.m., for a fire with flames showing through the roof of the building. A second alarm was called right away.

Degrane said the building, which was undergoing renovations, will need significantly more work now. He said the Fire Marshal's office will make a routine second visit to the site after repairs are made.  

"I would like to take this opportunity to thank all the firefighters and police officers that responded to the building fire at 385 Mendon Road. I appreciate all their efforts and hard work," wrote Jeffrey Kenyon, OD, of Blackstone Valley Eye Care, in a comment on the article reporting the fire. "We are excited to begin the reconstruction process and look forward to seeing patients in the renovated building early in 2013. I thank everyone for their support," Kenyon said.