Police, with the assistance of Air Wing, Search and Rescue Squad and SES, are currently searching the Kinglake area for missing man Justin.
The 35-year-old was last seen leaving Crossdale Green in Craigieburn about 9pm on 5 August.
He contacted family last night on social media saying his vehicle, white Mitsubishi Triton utility with registration 1FN5YU, became bogged in the Kinglake area.
Justin is described as having brown hair, blue eyes and a large tattoo of an eagle on his neck.
He was last seen wearing a black jumper, black tracksuit pants and orange runners.
Police and family have concerns for his welfare due to his disappearance being out of character.
Investigators have released an image of Justin and his vehicle in the hope someone has any information on his current whereabouts.
Anyone with information on his whereabouts is urged to contact Mansfield Police Station on (03) 5775 2555.