Police are appealing for public assistance to help locate missing man George Berger.
The 84-year-old was last seen on a blue mountain bike on Underhill Court in Sunbury about 8.30am yesterday.
He is of Caucasian appearance, about 162cm tall, bald, unshaven and was wearing blue jeans and runners.
Police have concerns for his welfare due to his age.
Police have released an image of George in the hope someone recognises him and can provide information regarding his current whereabouts.
Anyone with information about George is asked to contact Sunbury Police Station on 9744 8111.