Durham Police is mounting its biggest ever security operation for the visit of US President George Bush this week.
Residents in Trimdon are seeing increased security activity
All leave has been cancelled and 1,300 officers will be involved in the operation, which is expected to cost around £1m.
Mr Bush will spend most of Friday in Prime Minister Tony Blair's Sedgefield constituency as part of his state visit to Britain.
In the run-up to the visit, the former mining community of Trimdon Colliery has been besieged by British and American security officials.
They have been mounting extra patrols around Mr Blair's constituency home, Myrobella House.
Drains, neighbouring properties and cars in the area are all being searched by police.
In a statement on Monday, Durham Police said: "The biggest ever security operation mounted by Durham Constabulary is being drawn up ahead of this week's visit to the county of United States President George Bush and his wife Laura.
PRESIDENT BUSH'S ITINERARY
Tuesday 18 November - Arrives and receives private welcome at Buckingham Palace
Wednesday 19 November - Meets Michael Howard and Charles Kennedy, gives speech on transatlantic alliance and meets UK families of 11 Sept victims before attending royal banquet with Queen
Thursday 20 November - Meets British soldiers who fought in Afghanistan and Iraq, holds meetings with Tony Blair at Downing Street and hosts dinner at US Ambassador's residence
Friday 21 November - Travels to Tony Blair's Sedgefield constituency to meet members of the public before returning to Washington
"The force has cancelled all police leave as the finishing touches are put to an operation that will involve 1,300 officers, some of them drafted in from neighbouring forces."
It said Mr Bush is due to arrive in the north-east of England on 21 November and then switch to Mr Blair's Sedgefield constituency.
The operation in Durham is expected to cost about £1m and the force is talking to the Home Office to recoup the cost.
Assistant chief constable Gary Barnett, who is leading the operation, said the Durham force will have overall responsibility and officers from the Metropolitan Police are providing advice and support.
He said while there was no specific threat in relation to the visit, there would be a heavy police presence on all proposed routes and around the sites to be visited.
He said: "We have no indication at this stage of the size and scale of any marches or protests that might be planned in County Durham.
"However while we are mounting an operation to cover a very wide range of contingencies, we are looking to balance the needs of security against people's right to demonstrate peacefully.
"Road closures will be kept to an absolute minimum, but if roads have to be shut down for any substantial time, we will try and give local people as much advance notice as is operationally prudent."
He said officers were being briefed on security issues and the statutory powers available to them including provision to stop and search vehicles and pedestrians.