The wife of a Perth grandfather who has been missing for four days has made an emotional plea for people to help find her husband.
A police search involving 100 officers and SES volunteers is underway south-east of Perth for Ian Collett, 65, who has dementia and was reported missing from his home in Canning Vale on Saturday afternoon.
He was last seen walking along Albany Highway in Mount Cooke, south of Armadale, at midnight on Saturday.
His wife Deborah said she was grateful for the public's help so far.
"There are so many people looking for him and we appreciate that from the bottom of our hearts," Mrs Collett said.
"If anyone sees him or recognises him, please contact the police.
"We miss him and we want him back."
Mr Collett is wearing a medical bracelet that has his name, the word "dementia" and a contact phone number printed on it.
He has a house key on a green tag with his wife's number attached in his pocket.
Police believe he may have hitchhiked to Mt Barker, north of Albany in WA's Great Southern region.
They say he worked in the area in the 1980s and also has relatives in the region.
Anyone who sees him is asked to stay with him and contact police on 131 444.
