Huge 'explosion' heard across Hemel Hempstead was caused by fighter jets
Thousands of people were woken early on Sunday morning to the sound of a huge explosion across Hemel Hempstead.
Metropolitan Police have now confirmed it was caused by RAF planes.
Two Typhoon jets were scrambled to an aircraft which had lost communications and caused a sonic boom.
The RAF said the fighter planes were deployed from RAF Coningsby in Lincolnshire shortly before 4.10am.
The aircraft were the cause of an explosion-like sound which was heard across vast swathes of the South East, with Hertfordshire Police receiving a ‘large number’ of calls.
A spokesman said: "We have taken a number of calls from people reporting a loud bang in parts of the county.
"We would like to reassure you we have not had reports of an explosion or any other incident which may have caused this."
Some Hemel residents thought the bang could have been Buncefield-type explosion, which famously went up in flames in 2005.
One social media user, taking to Twitter said: "I heard it, assumed it was thunder but then thought it was a strange one off.
"I then wondered if it was a Buncefield-type explosion. Sonic boom makes sense."
Another added: "It shook my bed it was so loud. It’s concerning not knowing what caused it."
An RAF spokeswoman said: ‘Two Typhoon fighter aircraft from RAF Coningsby were scrambled at 0409 this morning, as part of the UK’s Quick Reaction Alert procedures, after an aircraft lost communications in UK airspace.
"The aircraft was intercepted and its communications were subsequently re-established.
"The Typhoons are returning to their base."