Hampshire Police have issued a further urgent appeal for missing Rosie Johnson, 22.
Rosie – from Glasgow – works at the Little Canada, a popular adventure centre in Wotton.
She was last seen at the centre on Sunday evening – and volunteers are now combing the area around nearby Wotton Creek.
Cops confirmed her family are being supported and kept up to date with the search.
Inspector Andy MacDonald said cops are now “seriously concerned” about Rosie’s welfare.
Rosie has mousey brown hair and is of slim build – and pictures of her have been widely shared with locals.
She was last seen wearing a dark blue puffa jacket and trousers.
Cops are being supported by volunteers from Isle of Wight Search and Rescue, Hampshire Search and Rescue and the Coastguard.
She is believed to have left the adventure park with no money or phone.
Inspector Andy MacDonald said: “We have serious concerns for Rosie’s welfare.
“Information suggests she is still on the island so this is where we are focussing our search.
“However, we would ask anyone with any information about her whereabouts to contact us as soon as possible.
“I would like to repeat our request for members of the Wootton community and surrounding areas to check any sheds, outbuildings or boats.”
Ryde Rescue have also been tasked along with two of the Island Coastguard search and rescue teams from Needles and Bembridge.
Inspector MacDonald added: “Please carry out a thorough search and call us on 101 if you think you see or find anything that could assist our search
“Residents will notice a lot of activity in the area today while we carry out our enquiries.
“If they have any concerns, they are encouraged to come and talk to us.”