Police say they are as mystified as everyone else as to the cause of a loud bang heard across large parts of Kent last night.
People living in Medway, the Isle of Sheppey, Deal and as far north as Bromley and Beckenham reported hearing the noise.
One Rochester resident took to social media to say the bang was so loud that birds flew out of a tree.
Police said they had members of the public report a loud bang at 8.35pm, but their inquiries had failed to reveal the source.
There is speculation that the noise may have been caused by a sonic boom.
A spokesman for the RAF said: "RAF aircrew are subject to stringent control over the use of supersonic speed over land and are only authorised to go supersonic when it is deemed absolutely necessary for operational reasons.
"We are not aware of any RAF aircraft doing so over Kent yesterday."
The Ministry of Defence's Shoeburyness site in Essex, which tests weapons and military equipment, said no explosive activity was expected yesterday.
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