Strange Lights Seen Over Indiana

An interesting post on Reddit featured a video of strange lights filmed over Greenwood, Indiana on June 21, 2015.

Before you freak out about UFOs and chem trails (no judgement) an explanation was provided in the comment thread that explains the phenomena:

"So what you are seeing is sunlight reflecting off ice crystal faces that are constantly being oriented by the developing electric field just above the [cumulonimbus] top. Then there is a discharge in the cloud, and the field collapses momentarily, and the crystals begin to realign again. Then this just keeps happening over and over."

I'm going to have to take their word for it because I know zip about electric fields or cumulonimbus tops.