Weird 'sky squid' UFO filmed from airliner

While most UFO videos tend to show points of lights, mysterious triangles or flying discs, every now and again a sighting emerges involving an object so peculiar that it almost defies description.

Reportedly filmed from the window of a commercial airliner between Phoenix and Portland, this bizarre video clip was recorded in March 2019 but was only posted up on YouTube a few days ago.

It shows what appear to be two smoke-like trails moving and weaving around in the air miles from anywhere, before coming together to form a single long trail that covers quite a distance.

Since being picked up online, the footage has attracted quite a bit of attention and has left social media users scrambling to come up with an explanation.

Suggestions put forward have ranged from an "interdimensional creature" to "the contrails of a single, twin-engine ket aircraft in a shallow climb as it ascends above minimum contrail level."

The anomaly is certainly too high up to be a drone and it's difficult to make out any aircraft.