"I drove by to get some food and noticed something flashing in the store," Sparks said in a blog post for the station. "It seemed weird, but only because the store had closed and it was a holiday; were people really still cleaning out the store?"

He later returned after eating to find the baffling phenomenon continued. Sparks was able to record a video of the event, which he posted to Snapchat and Instagram.

"After I ate, I drove back by and noticed the lights were still flashing," he explained. "So we pulled in the parking lot and that's when we noticed it was all the checkout lights--the signs that say what lane number--flashing in a random sequence...without ANYONE around!"