A suspected Second World War bomb thought to contain up to 1,000lb (450kg) of explosives which caused the evacuation of 55 people was actually a disused fuel tank, police said.
The discovery of the “bomb” on a building site shortly before 3pm on Wednesday in Peacehaven, Sussex, led to the closure of schools and roads.
Temporary accommodation was provided for those who were forced to leave their homes, with Sussex Police saying dozens of people were being housed in rest centres in the town.
But on Thursday morning, the force said on Twitter: “Explosive Ordnance Disposal experts have now identified the suspect WW2 bomb in #Peacehaven as a fuel tank.”
And Superintendent Jane Derrick said: “I’m sure everyone is relieved that this incident has been safely resolved, and I’d like to thank everyone affected for their patience and understanding.
“In such situations safety is always paramount. Unfortunately no one was able to determine exactly what we were dealing with until painstaking work by bomb disposal experts throughout the night confirmed there was no danger.”
The A259 South Coast Road has reopened, those evacuated returned to their homes and a 200-metre exclusion zone lifted.
But Peacehaven Heights and Telscombe Cliffs primary schools, and Peacehaven Community College, which had been closed as a precaution, will stay shut for the rest of the day.
Towns and villages across Sussex towns were bombed during the War with hundreds of civilians killed.