The Defense Advanced Research Projects Agency, better known as DARPA, tweeted an appeal Wednesday.
"Attention, residents of the city!" Tweets. "We are interested in identifying underground city tunnels and facilities that are owned or operated by a university capable of conducting research and experimentation."
"This is a short notice," they admitted. "Please respond by August 30 at 5:00 PM ET."
Attached were a series of photos – a dimly lit parking garage, an underground bunker with a field plate and an empty metro station – and a link to the official government website proposal .
People were understandably suspicious.
After all, these are the people who brought us a stealth weapon, an M1
The Department of Energy did not respond to a CNN request for comment.
DARPA, however, told CNN that Tweets had nothing to worry about.
" DARPA published a request for information last week, searching for underground urban tunnels and facilities owned or operated by the university, and yesterday's social media posts were a reminder of the impending response deadline, "Jared B. Adams, DARPA's chief communications officer, told CNN.
Think of autonomous robots scampering down underground corridors looking for bad guys.
"Complex urban underground infrastructure can present significant challenges in situational awareness in time-sensitive scenarios, such as active combat operations or disaster response," Adams explained.
So the next time you find yourself exploring an abandoned tunnel deep under an American city and something hiding, don't worry, it's an autonomous cave robot killer.
Just get moving. Quick.