Police at Craigieburn are investigating the theft of an electronic tablet which occurred in Craigieburn on 30 January.
Investigators believe the woman who had a dog with her as well as a teenage girl and boy approached the counter at a train station about 10am.
When a staff member walked away from the counter, it is believed the woman reached in and removed the tablet from inside the collection turnstile.
She passed it to the boy who then placed it in a backpack and he walked away, while she remained at the counter.
The woman is described as Maori in appearance with a solid build and dark hair in a bun.
At the time, she was wearing denim shorts and a black shirt and was carrying a backpack.
Investigators have released CCTV images of the woman who they believe may be able to assist with their enquiries.
Anyone with information is urged to contact Crime Stoppers on 1800 333 000 or submit a confidential report online at www.crimestoppersvic.com.au
