Police are focusing on the rural areas of Toolern Vale and Gisborne.

Missing Persons Squad detectives, Search and Rescue members, Mounted Branch, Air Wing, uniform members and the Dog Squad with the assistance of a cadaver dog are involved in the search.

SES volunteers will also be assisting and searching an area spanning from Blackhill Road to Gisborne Road.

Police are appealing for assistance from anyone who lives in the area to consider checking their properties for any changes or any suspicious activity since the disappearance of Karen.

Karen was last seen at her home address on Oakley Drive, Avondale Heights, about 10am on Wednesday, June 29.

She is described as 160cm tall, slim build, shoulder length brown hair.

She was last seen wearing a black jacket and jeans and it is believed she had a Coach handbag and a Coach purse with her.

Anyone who sees Karen should contact triple-0 or if you have information, contact Crime Stoppers on 1800 333 000 or submit a confidential crime report to www.crimestoppersvic.com.au

- with 3AW