Police in Northern Ireland ordered the evacuation of more than 400 homes to remove what is suspected to be a World War II-era bomb.
The removal operation could take more than five days, police said on Sunday.
The device was discovered on Friday in Newtownards, an area of County Down, about 15 kilometres east of Belfast.
"I appreciate the disruption that this has caused, however keeping people safe is paramount and we will not take any risks," North Down and Ards District Commander Superintendent Johnston McDowell said.
"I want to thank those who may be affected for their patience at this time."
Police had set up barricades and asked drivers to avoid the area.
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An emergency support centre was set up for residents who had to move out of their homes.
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