In the The Mothman Prophecies, John Keel documented that several people received mysterious phone calls that only had beeping or loud screeching noises when they answered them during the 1966 Mothman Flap. Other calls were interrupted by static or disconnected entirely. The problems were not limited to phones, police radios and televisions were also affected in the area of Point Pleasant, West Virginia in 1966.
Other weird calls to Keel during this time were credit to Indrid Cold, sometime thought to be a Grinning Man, sometimes an alien, often telepathic, always creepy.
I got a odd call and message today, left on my (571) 24WEIRD voice mail.