A 71-year-old woman arrested on suspicion of murdering missing teenager Gaia Pope has been released by police while inquiries continue.
Gaia, 19, from Langton Matravers, Dorset, disappeared from nearby Swanage on 7 November.
Police arrested the woman and a 19-year-old man, who are both from Swanage and know Gaia, on Monday.
Dorset Police said “extensive searches” would continue in the hope she is still alive.
The 19-year-old man remains in custody.
Police made the arrests after searching two addresses in Swanage late on Monday afternoon.
Police said a search for Gaia with the coastguard, volunteers from Dorset Search and Rescue and Wessex 4×4, along with members of the local community, was continuing in the Swanage area.
Det Supt Paul Kessler said: “We still believe Gaia somewhere in the Swanage area… I remain hopeful that we will find Gaia alive.
“If the public can help us – anyone who has had contact with her in the last seven days, please contact Dorset Police as you may have information that can help us locate her.
“However, we will continue to conduct every avenue of inquiry which is open.”
Gaia was last seen by family friend Rosemary Dinch at an address in Manor Gardens, Morrison Road, Swanage at about 16:00 GMT.
She told the BBC Gaia had “pounded” on her door then spent 20 minutes with her.
“She was very upset, she slid to the floor at one point, I gave her a cuddle and she responded to me – I have no idea where she is – she just seems to have disappeared,” she said.
Gaia was said to be wearing a red checked shirt with white buttons, grey and white woven leggings and white trainers.
She has severe epilepsy and she went missing without her medication.
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 force said Gaia’s family were being supported by specially-trained officers.