The investigation at a property in Ingleby Barwick has continued today as fresh pictures from the scene have emerged.
Pictures from the scene at Brading Court still show a large number of police vehicles present.
Emergency services first descended on the home yesterday at 4.30pm (February 6).
At one stage there were two fire appliances, seven fire brigade vehicles, along with several police patrol cars and riot vans and ambulances.
Police confirmed that they were at the property after the discovery of an "unknown substance".
It comes as 52-year-old Thomas Kwan, of Brading Court, Ingleby Barwick, has been charged by Northumbria Police with attempted murder.
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Today it has been solely police in attendance, including a specialist search team.
Here are pictures of developments today:
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