Police divers were this afternoon searching a pond at Godlingston Wood, a nature reserve on the outskirts of Swanage, though a police spokesman stressed that had no specific intelligence to say Gaia is there.
The 19-year-old reportedly began to take off her clothes at the home of Rosemary Dinch, telling the 71-year-old: 'I'm too hot'.
In a local BBC interview on Monday, Rosemary said that Gaia had knocked on her door when she was "very upset". 'I have no idea where she is, she just seems to have disappeared'.
'It was just an ordinary day, then she disappeared.
Mrs Dinch and Nathan have since been released under investigation. Forensic testing is still being undergone at both Elsey and Dinch's addresses.
Detective Chief Inspector Neil Devoto, who is leading the investigation, said: 'It has been nearly a week since Gaia's last confirmed sighting and she has not been seen or heard from since.
He said: "We have looked through CCTV that covers the Swanage area, including transport hubs, and there is nothing to suggest she has left the area".
'I saw Gaia, I think she was good friends with Nathan. "URGENT, PLEASE SHARE!", he wrote.
Gaia Pope is a teenager from Langton Matravers, Dorset.
Reporting Rosemary's account of the incident, ex-husband Greg Elsey, 69, said: "Gaia went in and stripped off the top half of her clothes down to her bra".
She has severe epilepsy and she went missing without her medication.
Forensic teams are now investigating the home Rosemary shares with son Paul, 49 in Swanage, Dorset.
Gaia Pope has not been seen since Tuesday 7 NovemberWho is Gaia Pope?
Dorset Police have now revealed they believe Gaia has "come to harm".
With no further information on the whereabouts of Gaia, police are still urging anyone with information to come forward.
Missing person posters were put up in Dorset on Tuesday afternoon as police reiterated their appeals for information.
On Saturday, Dorset Police released CCTV footage of what they believe was Gaia running past a house in Morrison Road at about 15:40. The footage was taken less than an hour before she was last sighted, and can be seen wearing a black jacket in the footage which the Mirror reports was later found at the home of Rosemary Dinch.
The force said Gaia's family were being supported by specially-trained officers.
Dorset Police said a 19-year-old man and a female pensioner were arrested in connection with the disappearance of Gaia Pope.