A slimy, pulsating blob living beneath the streets of North Carolina is not an extraterrestrial "sewer monster" as first feared.
It is, instead, a colony of prehistoric creatures called bryozoans — thousands of worms — that eat using a set of brown tentacles, the Charlotte Observer reports.
The harmless worms, moving around 10cm a day, normally live near ponds although environmental inspector Ed Buchan said the phenomenon was rare to see.
The blob was captured on film by a maintenance company doing a routine inspection on the sanitary sewer, which is located beneath one of America's oldest shopping centres.
A two-minute video showing the worms throbbing and contracting when shone with light made it to YouTube, sparking conspiracy theories about aliens and extraterrestrial life.
News outlets also went monster-crazy with headlines like: "Sewer monster is this summer's Susan Boyle" and "Mystery life form ... looks like heart meat!"
A spokeswoman from Malphrus Construction, the firm that shot the video, said the blob was the size of a golf ball and appeared much larger on video.
Authorities will not remove the blob as it is not clogging the pipes.