The "alien creature" conspiracy theorists on Twitter are running wild after a video appears to show an out-of-this-world figure walking near cop cars during an emergency response ... and we now have some answers as to what really went down.

Here's the deal ... a growing conspiracy theory online suggests the massive police response on New Year's Day in Miami isn't what it seems. Folks are pointing to one specific piece of footage they say shows a strange figure moving near police cars.

The person who posted the video says he zoomed in on some TikTok videos and claims he found a "gray creature."

However, spokesperson for Miami PD tells TMZ … "What is seen on this clip is the shadow of someone walking. If you look at the bottom of the shadow, you can see the person. No creature."

So that's that ... and as for how the whole thing started, folks thought the sheer number of police cars at the scene seemed to be way more than necessary. Cops were called to the shopping mall over a group of teens fighting, launching fireworks and causing chaos at the mall ... but there's reports some thought the fireworks was gunfire, which likely triggered the massive police response.