Police confirmed officers were notified of a suspected ordnance device being found on the beach near Western Road, Lancing, around 10am today.
A cordon was set up as a precaution and the Explosive Ordnance Disposal (EOD) was called to carry out an assessment at the scene, police said.
Sarah E Parker, who noticed police cordoning off part of the beach from her window while she was working from home, saw the bomb disposal team arrive and carry out the controlled explosion.
The historian, who said she had always been interested in the second world war, said: “There was a massive blast and the sea went high into the air. It was quite breathtaking.”
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