CHICAGO HEIGHTS, Ill. — The Federal Bureau of Alcohol, Tobacco and Firearms has joined the investigation into a massive warehouse fire Monday morning in Chicago Heights.

According to WGN-TV in Chicago, a spokesperson for the south suburb declined to say whether investigators have found any evidence that causes them to suspect arson. 

According to a statement, “Given the scope of the blaze and the depth of the agency’s resources, the Bureau of Alcohol, Tobacco, and Firearms (ATF) will lead the investigation in conjunction with the Illinois State Fire Marshall. Chicago Heights’ fire and police department personnel will also be working with the ATF and State Fire Marshall’s investigation into the cause of the fire.”

The blaze broke out Monday around 6 a.m. at the Morgan Li manufacturing plant and flames quickly consumed the 500,000-square-foot facility. No one was inside the plant at the time and no injuries were reported.