Police divers have been called in to help search for missing grandmother Pamela Jackson.
The North West Dive Team and Humberside Dive team have been searching Blackstone Edge Reservoir and Baitings Dam in a bid to find clues for the 55-year-old.
Two teams from Durham Police are also still combing the moors of Calderdale in the Ripponden and Cragg Vale area.
And the police helicopter has been called out to the scene with two members of the military to take aerial pictures this week.
Ms Jackson vanished from her home in Chester-le-Street, County Durham, on March 2.
Her partner Adrian Muir, 50, from Halifax, has appeared in court charged with her murder.
Sargeant Rachel Stockdale, from Durham, is the police search advisor and is co-ordinating the operation as well as feeding back information to Durham.
“This has always been the long strategic plan to introduce the water at this stage and to get the military back,” she said, “It is a long process but we need to eliminate this area. We have carried out extensive searches in Durham but we may well revisit the area.
“We will be leaving today but will return on Monday with another two teams coming up to do the land searches and we have the dive teams continuing on with the water.
“It is a slow process but it has got to be systematic to make sure the search we do, we do to a high level.”
A spokesman for Durham Police said Pamela’s family were aware of the work of the search teams and that it may continue for some weeks. “They will be kept informed the moment there is any development.”
Watch our video of the drivers searching the reservoir.