In Oregon, residents near Forest Grove have for weeks been reporting an unusual, shrill noise that reportedly occurs at all hours of day and night.
Those affected by the noise have complained that the high-pitched "whistling" sound has led to many sleepless nights, with some likening the noises to metal scraping, or the screeching noise of brakes being applied.
The mystery noise has been recorded by Forest Grove locals, and featured in a number of newscasts that have featured the strange sounds, though as yet no explanation appears to have been offered.
The Oregon "mystery noise" can be heard in the video below:
Earlier last year, a similar sound was being reported near Belfast, Northern Ireland, by a YouTube user identified as "PythonGuy", who asked whether anyone could identify the noise. “I have also heard thumping and screeching sounds and it always sounds like it is coming from the sky. It also seems to affect the birds when they are flying, causing them to dip and almost hit the ground when the sound it is at its highest," the uploader reported in comments with the video.
The Belfast "mystery noise" can be heard below:
Comparing the sounds present in the two videos, one will note a rather remarkable similarity that exists. The pitch of the noises, recorded in separate parts of the world, and several months apart, do appear to be nearly identical, with the exception of the fact that the noise recorded over Belfast appears to have remained consistently (and reportedly for more than an hour), whereas the sounds recorded by Forest Grove residents appears to occur intermittently, but still carrying a similar tonality.
Some have suggested the sounds recorded near Belfast had been a siren emanating from the Palace Barracks, is a British Army installation in Holywood, County Down, Northern Ireland. However, this would not explain its similarity to the noises reported by Oregonians over the last few weeks.
Forest Grove officials believe that brakes applied by trains are not a factor, as the nearest train tracks are seldom used. Similar "mystery noises" in the past have turned out to be the result of trains operating nearby, as well as metallic graders, as had been the case with an incident reported last year near Terrace, British Columbia. Other possible solutions to the mystery may include some variety of atmospheric phenomenon, though it remains unclear at present what sort of meteorological event could result in such noises.
Have you heard noise similar to those described here, as featured in the two video clips above? Send your observations along to us via email, or using the comments section below.