Fred West investigation: Police may speak to Rose as six 'voids' found at Gloucester cafe in Mary Bastholm search
Six "voids" have been found in the basement of a Gloucester cafe at the centre of a Fred West investigation.
The Clean Plate cafe in the city centre has been linked to the disappearance of 15-year-old Mary Bastholm.
The teen went missing in 1968 and the case has long been linked to serial killer Fred West.
Mary worked at the cafe, then known as the Pop-In cafe, as a waitress and West was a regular customer.
After being alerted to "possible evidence" of human remains by an ITV documentary team, police began an investigation at the cafe last week.
On Monday 17 May, the force revealed they would begin excavation work.
Speaking to ITV News West Country presenter Jonty Messer on Tuesday 18 May, Detective Chief Inspector John Turner said there are "structural anomalies" at the site.
Watch ITV presenter Jonty Messer's interview with Detective Chief Inspector John Turner
'Blue material' found
Police sent dogs in as part as the investigation and Det Ch Insp Turner said there are six "voids" in the cafe's basement.
He said a drill hole was made into one void so dogs could sniff the area, adding: "The dog gave a minor-medium indication that there was something of interest down there.
"An endoscope was put in one of the holes and now from a grainy picture which I've seen, it looked like there was blue material within the void."
Mary was wearing a blue coat when she went missing and so police will now excavate the area.
Det Ch Insp Turner said: "What I'm not saying is we've found Mary, I'm saying we've found a bit of blue material and with the back story around what's been going on, gossip, rumour, folklore over the years, this has provided me and most importantly the family a chance to understand for sure what is in that basement.
"I want to know for the family what is and isn't in that basement, so I've made the decision we will be excavating all six voids so we can know for sure what is or isn't in the basement."
He told ITV News West Country police are confident they will know "one way or another" if Mary is there after excavation work but that "Fred is the only one who really knows".
Fred West took his own life in prison while awaiting trial for murder. His wife, Rose West, is in prison having collaborated with him in the torture and murder of at least nine young women between 1973 and 1987.
Ch Insp Turner told ITV News the force "may speak to Rose" depending on what they find.
He said: "If we find anything of significance we will then clearly review what we've got, we will have a forensic recovery of what we get and then I will consider what and who we need to speak to in due course."
Police say the excavation is likely to take two weeks.
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