The Mutual UFO Network (MUFON) has been sent a video clip by a stunned unnamed witness who claims to have recorded the fabled craft flying over a major highway.
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.
In the video, which lasts nearly two minutes, an apparent black triangle shape is seen slowly moving silently in the sky. It appears to have large pulsating red and green lights, like many previous alleged TR-3B sightings.
Later there appear to be three lights visible.
Two men are heard talking in amazement about what they see, initially whispering, but becoming increasingly louder and excited.
One man says: “What is that? It is not even moving. Dude, holy c**p, that’s weird.
“What the heck dude? What the f*** is this?
“Dude, look at this thing, it is not even f***ing moving. Dude, it’s f***ing triangular. Holy s*** dude, that is some wicked s***.
“Dude, you got your camera? Holy s*** there’s no noise. That is not a helicopter.”
In a brief report to MUFON, which is the world’s largest UFO investigation organisation based in the US, the witness said: “Triangular UFO hovered over route 45 in Mantua, New Jersey, and turned on its side over the road, and then flew sideways towards Philadelphia.”
He described the craft as flying extremely slowly, at just around 10 miles per hour.
He said: “I have never encountered any aircraft like this in my life.
“It made no noise and it seemed to have multicoloured lights rotating inside one light.
“Did anyone else witness this at approximately 9:40 pm on June 10th 2016?”
Conspiracy theorists have long claimed the TR-3B Black Mantra is an alleged stealth reconnaissance nuclear-powered triangular shaped craft.
Previous conspiracists have claimed the Black Mantra was developed by the US under a cloud of secrecy in the 1970s, but its existence has never been proved.
Over the years, there have been dozens of reported sightings of mysterious-shaped aircraft in Antelope Valley in the Californian desert – an area known to attract Black Mantra hunters as it is near several military research and testing zones.
But, until now, no clear video footage had been captured.
Conspiracists believe the TR-3B Black Mantra is not the first of its kind and is, in fact, a successor to an earlier TR-3A craft.
There are longstanding rumours about the existence of reconnaissance airplanes of the US Air Force under so-called “black projects”.
According to conspiracy theorists, the TR-3A Black Manta is a subsonic stealth spy plane designed by Northrop Gruman and was allegedly used in the Gulf War to guide F-117A Nighthawk bombers.
However, there is no proof or direct evidence of the existence of any of the alleged spy planes.
Last June YouTube UFO channel Secureteam 10 released a video claiming to have found a Black Mantra craft sitting in a crater on the moon in images obtained from a camera mounted on the Lunar Reconnaissance Orbiter (LRO) spacecraft.
Earlier that month, Secureteam also posted a video claiming they had found similar craft in NASA images of Dwarf planet Ceres.
But the were widely panned as being an odd-shaped rocks.
MUFON confirmed it is investigating the new footage.