Early Thursday morning, a strange mystery sounded in St. Paul. Many residents in the Highland Park area woke up before 5 a.m. to eerie howling and crashing noises near the frozen Mississippi River.
The sound began waking residents as early as 4 a.m., and the noise echoed for miles -- so what was it?
The Army Corps of Engineers believes they may know the answer. Although many initially suspected a demolition near Fort Snelling caused the odd commotion, officers sent to check out the source of the sound did couldn't link connect the two.
"I couldn't tell if it was an animal or some kind of train accident," Tim Nelson, a reporter with Minnesota Public Radio who recorded the aural oddity, told Fox 9 News.
Although some likened the sound to a whale song, others admit the spine-tingling tones seemed a little ghastly.
"It sounded like a ghost. It sounded like a moan. I expected some specter to rise up out of the river and walk through Highland Park this morning," Nelson said.
Although no one has pinpointed the exact cause of the haunting hubbub, Aaron Buesing, of the Army Corps of Engineers, said moving ice on the frozen Mississippi River is probably making the racket, possibly as it rubs against piers.