A trucker claims to have seen the heavily guarded convoy, with a triangular-shaped craft in tow, at night just about 100miles from the top-secret US Airforce base as the crow flies.
TR-3B is alleged by conspiracy theorists to be a secret “black project” spy craft of the US Government that can be flown into space.
The allegations are that these crafts are created at top-secret military bases like Area 51, in Nevada, by reverse engineering alien technology.
Others claim they are actual UFOs flown by aliens visiting Earth.
The man has filed a report about the sighting to the US-based Mutual UFO Network (MUFON), the world’s largest organisation dedicated to UFO and alien research.
He said he was driving north on route I-15 between Baker and Primm, California, at 11pm on Thursday, February 9, when he had the shocking experience.
He wrote: “Now let me start off by saying that this vehicle could very well be a secret military experimental aircraft.
“After some time I had noticed that there wasn’t any traffic heading south on I-15 for at least five minutes.
“A few minutes later as I was cresting a hill here comes the highway patrol with all their lights on driving somewhere between 80-100mph with the military in tow.
“They were all escorting a single flatbed trailer with an incredible somewhat triangular shaped UFO like vehicle on the trailer.”
He said it was much wider than the trailer and had three sets of landing gear in which it stood upon.
He added: “It was also covered in a shrink-wrap like material. It had markings on it but none looked familiar (no American flag or numbers that I could see).
“The colour of the material it was covered in was light grey, dark grey and black.
“Behind the truck carrying the object was more military vehicles and then about a half mile or so behind them were more state troopers keeping traffic back.
“I’ve seen many different UFO pictures and this object was close to being similar to the TR-3B but it’s edges were much more rounded and wider.
“I really wish I could have gotten a picture of it, but then again I’d probably have the military or some men in black paying me a visit.”
Area 51 is a heavily guarded base in the Nevada desert, where conspiracy theorists claim evidence of alien visitations are hidden away, or secret projects to design experimental craft take place.
This is not the first similar convoy sighting.
Last week Express.co.uk reported how a stunned eyewitness watched open-jawed as a “UFO” was apparently seen being transported by a police convoy on the back on a truck at night near the Fort Leonard Wood area of Missouri on February 1 at 10.15pm local time.
The alleged sighting was reported by an unnamed man to the National UFO Reporting Center (NUFORC) in the US.
It is about 240 miles from the Wright Patterson USAF base, which is where conspiracy theorists claim crashed UFOs, and even alien bodies, have been hidden away by the military.
Then, Scott C Waring, editor of ufosightingsdaily.com, said that video footage had emerged of the most recent sighting reported to NUFORC, from another source.
Andre Milne, is the founder of defence technology firm Unicorn Aerospace, which describes itself as “the world’s leading developer of advanced navigation technology.”
According to its website, Unicorn Aerospace is “committed to development of advanced aerospace technologies in order to maximise revenue stream growth potential into the respective markets of the private commercial and public military sectors.”
Mr Milne told Express.co.uk: “The semi circular UFO style aircraft being transported on the flat bed trailer in the video is in fact an advanced generation design of a long series of experimental aircraft called Flying Wing Bodies.
“In this design the main body of the aircraft is the actual wing of the overall aircraft itself.”
He also claims top-secret craft are developed at Area 51, but there is no evidence of aliens hidden there.