The 500lb explosive will be detonated in a controlled blast after it was found by workers near Rawcliffe Road, in Goole.
It means the nearby M62 has been shut down until midday on Saturday between junctions 35 and 37, while a no-fly zone has been imposed over head. Eight nearby homes have all been evacuated, a section of the A614 closed and a number of local roads cordoned off.
In a statement, Humberside Police said: “Colleagues from the Explosive Ordnance Disposal team, who have been onsite since [Thursday] night have now confirmed that the device is live and are making plans to safely detonate the bomb within the next 24 hours. All persons in the immediate vicinity have been evacuated as a precaution.”
They added that they hope the explosion would go ahead on Saturday morning.
The find has forced the cancellation of Goole's park run, which organisers had said would resume on Saturday after months of being on hold due to Covid-19 restrictions.
They said: "After all these months waiting it is very disappointing to have to bring you this news but hopefully we will be all systems go next week."
The disruption comes just three days after homes were evacuated in Wallasey, Merseyside, following the discovery of two suspected Second World War bombs in a garden there.
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