A meteorite could be lying in seas off south Devon after hurtling at thousands of miles an hour to earth from between Mars and Jupiter, according to experts.
On Thursday, police lines were swamped with callers reporting loud bangs and buildings shaking at about 4.15pm in parts of Devon and Cornwall.
Reports flooded in from Harrowbarrow in south east Cornwall, the South Hams and Teignbridge areas of south Devon, the Tamar Valley and Dartmoor.
The British Geological Survey said the noise could have been a sonic boom from a meteorite plummeting to earth.
Brian Sheen director of Roseland Observatory in Cornwall said with no evidence of an earthquake reported by the BGS, thunder or RAF jets in the area the only likely explanation was a meteorite.
He said: "It's really very exciting – a joining-up of us with space, so to speak.
"The meteorite is probably made of rock and iron and part of an asteroid orbiting the Sun between Mars and Jupiter.
"From the direction the sonic boom was reported to come from, my best guess is the meteorite is likely to be in the sea off the South Hams.
"As yet no one has found any bits which suggests it could be in the sea – but I would still urge people to keep an eye out and report it to me at the observatory."
Police staff in Devon's Newton Abbot station also said the floor shook.
Insp Gareth Twigg, of Devon and Cornwall Police, said the initial waves of calls reported sounds like an explosion.
He said: "Further calls also described noise and then objects shaking. One lady on Dartmoor who was alive during the Second World War said it was like a bomb going off.
"We checked with the British Geological Survey to ask if it was because of a tremor, but they said it may have been caused by something a little more spectacular – possibly a sonic boom from a meteorite as it caused pressure changes in the atmosphere while falling.
"It appears nothing has struck the earth that has caused any damage or injury."