An area of the beach at Hornsea was taped off yesterday following reports of an ordance on the promenade.
Bridlington and Hornsea Coastguard Rescue Teams were called to the beach and assisted Humberside Police in the incident at 10.50am.
The area was cordoned off to ensure public safety and it was later established that the item had been taken off the beach and placed onto a bin.
Hornsea Inshore Rescue assisted with a road closure on the south promenade.
EOD bomb disposal also attended scene and took the item away for disposal.
The coastguard has now issued a warning to the public following the incident.
A spokesperson said: "Do not take such items off the beach.
"If you come across anything you believe may be unexploded ordnance stay at a safe distance, dial 999 and ask for the coastguard."