It seemed to come out of nowhere.
Paul Dowd was sitting in his north side home Wednesday night when all of a sudden a huge crash sent him and his family running outside.
"We heard a big boom. The whole house shook," Dowd told the Chicago Tribune. "And I looked outside. I thought it was the "L," or something that, I don't know, exploded, or whatever."
Pieces of ice littered his yard, even though there had been no storms in the area. And on one corner of his house, an entire piece of his roof was destroyed.
The family called the police and decided after some discussion that the house was likely stuck by an ice bomb inadvertently dropped from one of the commercial planes that often fly over their home on the way to or from O'Hare Airport.
No one was hurt by the falling ice, police said.
The Federal Aviation Administration announced Thursday afternoon it was opening an investigation to see whether any planes flying overhead might have had a leak.