Camberwell police continue to appeal for public assistance and search for missing man Gregory.
The 70-year-old was last seen on Victory Boulevard in Ashburton on Thursday, 24 November.
Police and family have concerns for Gregory's welfare due to medical conditions and he can sometimes become confused.
Gregory was last seen wearing a brown corduroy jacket and pants and is described as having a thin build, long grey hair and a long grey beard.
He uses public transport and frequents Burwood McDonalds, service stations for coffee and the Ashwood, St Kilda and Fitzroy areas.
Investigators believe he was seen in the Forest Hill area and the Nunawading train station about 10am on Friday 25 November.
An image of Gregory has been released in the hope someone can provide information on his current whereabouts.
Anyone who sights Gregory is urged to call Camberwell Police Station on 9882 0688.