Lobo has lived with Jeff Wilson for more than a year and a half. The Army veteran works with Operation Freedom Paws, an organization that rescues dogs from shelters then pairs them with disabled veterans.
According to the group's Facebook page, Wilson just had knee surgery and couldn't run after Lobo when he got away.
The dog was last seen near Berryessa Road in East San Jose.
Anyone with information about Lobo is asked to call 408-833-2374 or 510-708-1895.