Work on the unexploded bomb in Great Yarmouth has come to a halt after the sand wall was compromised.
The Second World War bomb was reported to police on Tuesday after it was dredged out of the River Yare.
Water has reduced the integrity of the sand barrier built around the bomb and work is needed to repair it which may take a number of hours.
READ MORE: Live updates as work to defuse bomb enters fourth day
Once this is done, army specialists will continue cutting into the bomb.
Norfolk Constabulary's assistant chief constable Nick Davison said: "We understand this has been an incredibly slow process but it’s needed to be for the safety of the public and those involved in disarming the device.
"We’re hopeful a significant part of the operation will be finished today and we will keep the public updated."
A 400-metre cordon remains in place with a strict 200-metre inner cordon that people are banned from entering.
A no-fly zone in the immediate vicinity of the device was put in place on Wednesday and will remain until further notice.
Great Yarmouth Borough Council chief executive Sheila Oxtoby said: "We are acutely aware how disruptive this has been.
READ MORE: Everything we know about the unexploded bomb in Great Yarmouth
"We are enormously grateful for the patience and understanding of those who have had to leave their homes as well as the wider community.
"The wellbeing of those displaced is our priority and if the situation carries into the weekend we will offer suitable, comfortable accommodation with all the facilities people require."
People who have been evacuated from their homes will find temporary care at Yarmouth Town Hall until 5pm today and they will then be offered overnight accommodation and support.
An emergency helpline has been set up for people who require assistance with evacuation and accommodation. This helpline is 01493 330369 and should not be used for general advice.
People concerned about their health or prescriptions left at home are being advised to call 111 for support.
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