The home of a hospital doctor in Staffordshire was being searched last night as part of the anti-terror operations.
Forensic experts and police officers swarmed around the house, in Sunningdale Grove, Chesterton, and removed black bags filled with items to be tested and examined.
The cul-de-sac was cordoned off and a tent was erected in the back garden of the property.
Neighbours said they believed the man, who lives with his wife and their young son, had moved to the area from Shrewsbury and was working at the University Hospital of North Staffordshire. Sunningdale Grove is a cul-de-sac of about 20 houses situated off the A34 on the outskirts of Newcastle-under-Lyme.
Neighbour Daniel Robinson said: "We have had a police presence here since 9.30pm Saturday night, which is still ongoing. The police have not told us anything.
"It's a rented property. The owners are away and the gentleman living there is a hospital doctor. They have been here for just over nine months. I have only occasionally met him. He seems a very, very pleasant man indeed. He speaks very good English."
Mr Robinson added: "It's fairly disturbing but at the same time I find it very hard to believe, having met the gentleman, that he's involved in any way in terrorism."
Another resident, Richard Holland, said: "We have been told that a vehicle pulled over by police up north had something to do with the house. He kept himself to himself. I know he had a wife and a young child. He never really spoke. He said 'Hiya' and nothing else.
"It's a surprise. We have been here 15 years and the area has seen nothing like this before."
Next door neighbour, Hayley Fryer, 20, said: "I have only seen him a couple of times - only at night, never in the day time. I have never even seen the woman."
The search was a joint operation carried out by officers from the Metropolitan Police, Midlands Counter Terrorism Unit and Staffordshire Police. A Metropolitan Police spokeswoman would not confirm whether the search in north Staffordshire was linked to arrests made on the M6 in Cheshire.
He said: "We are not prepared to say whether the search in Newcastle-under-Lyme has a direct connection to the arrests made on the M6. However the search and the arrests are part of an ongoing investigation into the attacks in London and Glasgow."
Chief Supt Steve Loxley from Staffordshire Police said: "Throughout this operation the the safety of all our communities has been the number one priority. It will continue to be over the coming days and long after the cordons are lifted and the media spotlight moves elsewhere.
"In spite of the current police activity, I do need to stress there is no specific threat to our county." He added: "However, we are not immune from the wider, very real terrorist threat faced by the UK."
