People living in Norfolk and Suffolk have taken to social media to speculate about what could be behind a loud bang heard across the region this morning.
The bang, which happened at around 8.40am, could be heard in Thetford, Diss, Rickinghall and as far away as Stowmarket and Ipswich.
People took to the streets to see what was taking place, with a number of people saying the noise woke them up and shook their house.
The RAF has confirmed that it sent fighter jets to escort an aircraft into Stansted Airport this morning.
What is a sonic boom?
A sonic boom is a sound that occurs due to shock waves created by an object travelling through the air at a rate faster than the speed of sound.
Sonic booms often sound like an explosion, due to the amount of sound energy generated.
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