A popular UFO site has released what it's calling the "best evidence" ever recorded of an alleged top-secret US military plane that may have been built using alien technology.
But the controversial claim is being widely mocked online, with sceptics saying it looks both like an ordinary passenger plane and a computer-generated forgery.
The dim and blurry footage, uploaded to YouTube by UFO Today, was reportedly shot in Oregon, US, on January 26.
"The footage captured a TR-3B UFO in mid-air," its caption reads. "This footage might be the best evidence ever of the TR-3B UFO ever."
The TR-3B is allegedly a top-secret nuclear-powered craft created by the US Government. They're triangular, typically with a solid light in each corner, and sometimes one in the middle. The second-ever episode of cult TV show The X-Files featured a typical example.
A common explanation for the mystery craft's amazing abilities is that it was built using alien technology.
In the new footage, captured on a dashcam, the craft can be seen flying low in the sky over a road at night.
"The triangular object [is] flying at a very low altitude which is very strange," the caption reads.
But the lofty claim it's the "best evidence" ever of the existence of the TR-3B is drawing guffaws from amateur UFO enthusiasts. The UFOs section of popular web forum Reddit was largely in agreement there was computer fakery involved.
"The composite CGI is sliding against the background plate/footage," wrote user AutomaticPython. "Dead giveaway of sloppy tracking in (special effects computer software) After Effects."
"The odd motion/tracking with the live footage tells me this is a big fat CGI hoax," added Smugallo.
Others pointed out the corner of the triangle at the back is flashing - just like a plane's would be, with the other two being the plane's landing lights - which also explains why it's flying so low.
It's also worth pointing out the craft in the video appears to be flying fast enough to be a plane, and doesn't make any sudden movements. UFO enthusiasts usually point to lights making 'impossible' manoeuvres as evidence they're not of this world. Nothing of the sort can be seen in this clip.
The blurry video makes determining what it really is impossible, but Occam's razor - the idea that the simplest explanation is probably the correct one - suggests it's likely just a plane.