Sad Day...

yesterday was a very sad day.  i put my dog in the backyard so i could go check a job and do a little home work where i could get internet access. so i left for about 20-25 min a came back to a small whole dug out from under the fence.  my dog was gone.  so i whistled for him and walked around the block, no sign.  so i got in my car and drove around the neighborhood calling for him and no sign of that black lab.  while i was driving i saw an animal control truck driving around, that gave me the idea to call the police to see if there was a report of a random dog.  i called them and there was none. they said if there was one they would give me a call. it is 10:30 the next day and still there is no sign from my dog. i am afraid that i have lost him for good...