Chile's Calbuco volcano erupted on Wednesday for the first time in half a century, but the enormous plume of ash and smoke spewing into the sky wasn't the only attraction as it seemed the rare event caught the eye of a UFO.
Photos and videos showed a mysterious glowing craft hovering mid-air near the eruption before it disappeared.
YouTuber Ana Luise Cid uploaded a video of the alleged UFO and described it as a "luminous object near the plume". She added: "Some believe it may be a drone or a police helicopter. What is striking, in my opinion, is that the object remained static, then vanished. Optical illusion?"
Now UFO researcher Marc Dantonio has spoken about the mysterious sight, believing it is most likely a drone.
Speaking to The Huffington Post, Dantonio said: "In at least one video of this eruption, you can see what I have identified as a definite drone.
"It appears to be a Phantom 2 drone, based on the lighting pattern. This drone was captured by several witnesses in a video compilation of five different videos of 'the UFO.'"
He adds: "In the compilation of those five videos, there is one that shows the two-sphere object from a different perspective and this new perspective indicates that the object/drone was far closer to the observers than to the volcano. I believe it was launched in the town and brought up to altitude where it held station to observe the ash plume."
The footage, which appeared to show a disc with lights on either side flying over the cloud line,was caught on video while the plane was flying over the capital.
There was a mixed reaction from YouTube users, with one writing: "Very convincing."
However, most people don't think it was some kind of alien invasion. One user wrote: "Why did they photoshop an oiler ship into the sky?"
Another wrote: "That is obviously a swamp gas or a weather balloon... and if it is indeed an unidentified flying object - then it would be an experimental aircraft or some sort or another."
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