Mysterious chunks of ice fell out of the sky and onto Dubuque, Iowa on Thursday. One 50-pound chunk fell through a woman's roof, others ripped through trees.

Authorities say that whether the ice dropped from a passing plane or formed naturally in the atmosphere that either situation was rare. That is good, because the falling ice chunks rattled residents.

"It sounded like a bomb!" 78-year-old Jan Kenkel told the Associated Press.

The 50 pound ice fell through her roof early, at about 5:30 a.m. It tore through her television room ceiling to land in a pile of shredded insulation and splintered wood, the AP reports.

Residents reported that the ice was pure white, which indicates it was not discharge from a passing plane's toilets. Experts said that skies above Dubuque were clear at the time and that ice formation of this type is usually associated with cold fronts, not warm summer temperatures.