A bomb squad unit carried out a controlled explosion after a "possible ordnance" was found on a beach.
The coastguard was called out to Old Hunstanton beach in Norfolk on Friday evening and put a cordon in place until the item was covered by the tide.
Members of the Explosive Ordnance Disposal team X-rayed it on Saturday, but the results were "inconclusive".
A controlled explosion took place at about 17:00 and a video was posted by the coastguard on Facebook.
Members of both Hunstanton Coastguard Rescue Team and the Wells and Cley team were involved in maintaining a large cordon around the area as the explosion took place.
In one video, as a loud bang echoed across the beach, a man could be heard to say: "That was more than I expected."
Following the explosion, the area was declared safe and the beach was reopened.