Homes have been evacuated while a bomb squad examines "several suspicious items" found by police after a row between neighbours.
Police were called to a house in Brentwood, Essex, over a dispute between residents in which a door had been damaged.
A man and a woman were arrested at the scene in Sawyers Grove at around 7.30am on Friday, Essex Police said.
When officers arrived, they forced their way into a property and found "a number of small items", the force added.
A police statement said officers were "continuing to work alongside partners to ensure the safety of residents following the discovery of several suspicious items at an address in Brentwood.
"Explosive Ordnance Disposal experts were called to the scene and are examining the items to establish what they are.
"Around 40 properties are affected, with occupants evacuated as a precaution."
The area cordoned off includes "much of Sawyers Grove and small parts of Sawyers Hall Lane and Highland Avenue.
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"Residents whose properties are within the exclusion zone can go to a rendezvous point at King George's Playing Fields Pavilion while the cordon remains in place.
"We appreciate the disruption this is causing and thank residents for their patience. We'll continue to provide updates and hope to have the cordon lifted as soon as possible," the force said.
(c) Sky News 2026: Bomb squad called and homes evacuated after 'neighbour dispute'
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