Labrador Retrievers

Question
I have 5 labs.  They dig under the chain link fence that I have.  I have tried a invisible fence.  Not only was it expensive but it didn't work.  Someone suggested putting barb wire under my chain link fence.  Will that work and will that injury my dogs?  My neighbors are getting impatient about them getting out.  They are threatening to shoot them if they get out again.

Answer
That is a common problem.  I have my fence lined with flagstones.  It was a lot of work, but by hauling the roocks from the quarry myself, it was dirt cheap.  Just make sure to use large ones.  Paving stones from a home center would go faster, but be more expensive.  

I would be afraid the dogs would shred their paws on the barbed wire.

With the stone partly under the fence, it reduces the grass growing up in the fence.