Startled Brits have reported hearing a “sonic boom” in parts of south England.
People from Cambridge to North East London have taken to Twitter to share their shock at a loud rumbling sound this afternoon.
Some have reported their homes shaking in the unknown blast.
“Bloody hell was that a sonic boom in Cambridge? Literally shook the house!” one said.
Another added: “Real window-rattler. My thoughts were sonic boom, too.”
A sonic boom refers to the loud sound made from the shock waves created whenever an object travels through the air faster than the speed of sound.