Electricity has been turned off to a number of homes in Sunderland as armed officers remain at a house.
Officers executed a warrant at the property in the Westlands area earlier, but have not said whether it was to carry out a search or an arrest.
Northumbria Police said electricity to the property had been switched off "as a safety precaution" but have not revealed any further details.
A Northumbria Police spokesperson said: “Shortly before 09:00 today officers executed a warrant at an address in The Westlands area of Sunderland.
“Police remain at the scene. Anyone with any concerns is encouraged to speak to an officer on duty.”