A man was taken to hospital after he was injured by what police say was a "homemade device".
Bomb disposal experts were called in to assist with an operation in Houghton-le-Spring on Wednesday 7 September, after a man suffered a serious leg injury.
Emergency services were called to the Newminster Close area at about 11:25am to a report of concern for the welfare of a man.
He had suffered a serious but non-life threatening injury to his leg, a spokesperson for Northumbria Police said.
They added: "Upon carrying out enquiries at the address, officers located what appeared to be a homemade device that caused the injury.
“A full investigation has been launched into the discovery, and as a precaution, officers are being supported by bomb disposal experts in order to ensure the device is safely removed.
“Police remain at the scene. There is not believed to be any wider threat to the public and anyone with concerns is encouraged to speak to an officer on duty.”
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