The residents of the council house, a 59-year-old woman and her 26-year- old son, were being questioned as the excavations took place.
Nicola Payne went missing on 14 December 1991 as she made a 10-minute walk from her boyfriend's house to her parents' house in Coventry. The house being searched yesterday was in Wood End, about 150 yards from Ms Payne's home.
Digging took place in pouring rain in three spots in the large garden, including an area under the garden shed, in patches where electronic equipment suggested that the soil had been disturbed. The police were being helped by a team who used radar machines to search the house in Cromwell Street, Gloucester, where the mass murderers Frederick and Rosemary West lived. The Coventry excavations took place in a garden 18ft by 100ft.
The operation, which involved 35 officers from the West Midlands Police, began at 6am when they went to the house with a search warrant. This followed new information passed to the police after an appeal in December about the missing teenager. Police said the two people at the house that they were investigating were "aware" of Ms Payne but refused to give further details.
Ms Payne disappeared at just after 12.10pm after leaving the home of her boyfriend, Jason Cooke, in thick fog. She had taken her seven-month- old son, Owen, to stay with his father as the couple made last-minute plans for moving into their new three-bedroom house the next weekend.
That day the area was enveloped in thick fog, and Nicola was last seen setting off into the mist across a piece of wasteland known locally as the Black Pad. Four years later, despite a massive police search, and a total of pounds 10,000 in reward money offered by her family and friends, no trace of her has been found.
Police said yesterday that Jason Cooke had been ruled out of the investigation.
Detective Superintendent Bob Minshull said that several potential burial sites had been found using radar and electronic probing equipment.
He said yesterday: "We have found several sites that we are now looking at closely. We have moved one of the garden sheds and lifted flagstones. So far we have found nothing but we are pressing ahead."
A police dog specially trained to search for human remains was used during the search, along with a ground-probing radar and electrical resistance equipment to search the soil for buried objects.
Any "hot spots" identified will be examined by Professor John Hunter, a forensic science archaeologist from Birmingham University.
The search may take up to four days to complete. Officers are also stressing that the operation is just one new line of inquiry in the case, and that nobody has been arrested.
John Payne, Nicloa's father, said: "Part of me wants to know so we can come to some conclusion and get on with the grieving process, but another part of me doesn't want to know the truth if it is bad news.
"If they do find anything it will be what I have always dreaded, but on the other hand at least I will know something for sure."
He said of the household being searched: "We know the family quite well because Nicola and their youngest son were at school together. My lad and their eldest son were mates."Reuse content