A man recorded a flashing light hovering over the famous Gateway Arch in St. Louis and can't explain what he saw.

Chase Rhoads witnessed the mysterious light while on break from work at about 2:30 a.m. earlier this week. He said that he's been out there every night the past month and never saw anything like it.

A surveillance camera from Malcolm W. Martin Memorial park recorded a second video of the light, saying "We guarantee you will be perplexed if you watch all 5 minutes of this surveillance footage!"

Neither the National Park Service nor the Scott Air Force Base had any reports of anything unusual.

Folks on Facebook are theorizing that the light was everything from a drone, to a weather balloon, to St. Elmo's fire, to the paranormal.

Read more on KTVI.