Royal Navy divers from Plymouth identified the object as a 1,200 kg unexploded German bomb dropped during WWII.

Two civilian SCUBA divers raised the alarm, resulting in the Royal Navy’s deployment. The weapon was then towed to deeper water and destroyed in a controlled explosion.     

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German bomb wwii
German bombs similar to the one found under teignmouth pier
Is there a high risk from German bombs in Teignmouth?

Bombs fell on Teignmouth during 21 air raids which occurred between July 1940 and February 1944.  However, almost all of these raids were ‘tip and run’ attacks carried out by solitary aircraft. Consequently, the bombing density over the town remained relatively low.

The German Luftwaffe’s SC 1,200 bomb contained 631 kg of Trialen high explosive. It was not often that the Luftwaffe deployed this particular model / weight of general purpose bomb. It is therefore a rarity to find an unexploded German bomb such as this in Teignmouth.