The man authorities say is responsible for a fire at an FAA facility is recovering in an Aurora hospital.
Police say the 36-year-old man is from Naperville.
An ATF source tells WGN-TV that the man was a disgruntled employee who was upset because he was being transferred to Hawaii.
According to our ATF source, he went down to the transmission lines in the basement and wrapped them in rags and soaked the rags in gasoline. He started cutting the lines as well. He was not attempting to kill himself, he accidentally cut himself and was burned in the process.
The air traffic control center guides planes after they take off it also ensures that arriving flights, and passing flights, stay far enough apart. The incident has caused thousands of flights at both O'Hare and Midway to be cancelled and delayed.
One employee was treated at the scene for smoke inhalation. No other injuries were reported.
Authorities have not charged the man at this time. They say they have not yet established a motive.
They also do not know when the FAA facility will be open.
This is a developing story. Check back for details.