Searches are continuing for missing teacher and mum-of-two Lindsay Birbeck who disappeared 7 days ago.
The 47-year-old was reported missing on Monday, August 12 and her family have described her sudden disappearance as "very out of character".
CCTV footage showed Lindsay, from Huncoat, at around 4.10pm on Monday (August 12) in the Burnley Road area walking in the direction of Accrington.
Officers believe Lindsay may have walked from Burnley Road on to Peel Park Avenue and from there into a wooded area known as The Coppice.
More than 100 people turned out yesterday evening (August 19) at The Coppice to help in the search for Lindsay.
The Coppice has become the focus of the police investigation, with drones and helicopters equipped with thermal imaging cameras searching the dense woodland.
Police have also searched the woods with its specialist dog unit, and have been assisted by mountain rescue volunteers and underwater search teams.
Officers have carried out house to house enquiries and have spoken to members of the public across Huncoat, but so far there is no trace of the 47-year-old.
Detectives are keen to trace a man seen walking a black Labrador who might have seen Lindsay in Peel Park Avenue, close to a pathway leading to The Coppice, between 4pm and 5pm on the day of her disappearance.
Lancashire Police confirmed that Lindsay's disappearance is still being treated as a missing person's enquiry and the man is wanted as a witness.
He is described as a white man, aged in his late 40s, 5ft 6in tall, of medium build with short dark hair and wearing glasses.
He is believed to have been wearing a dark jacket or coat and was walking a small black Labrador.
Detective CI Allen Davies said: "It is exactly a week now since Lindsay went missing and as time goes on we are clearly growing increasingly concerned for her welfare and Lindsay’s family are obviously very worried about her as her disappearance is very out of character.
"We have a large number of specialist police resources and partners assisting in our efforts to find Lindsay and I would encourage anyone who has seen her, or knows where she might be, to contact police immediately.”
Assistant chief constable Terry Woods added: "Our priority incident is the search for Lindsay Birbeck who has been missing for a week.
"We will continue to dedicate extensive resources to find her. Our thoughts are with her family."
Anyone who has seen Lindsay, or knows where she is, is urged to contact police immediately.
Anyone with information can contact police on 101 quoting log 0016 of August 13.
For immediate sightings please call 999.
Volunteers have also been busy handing out leaflets in the area and a community Facebook group called Lindsay's Search has now reached over 10,000 members.