Stolen Fence

What is the name of your state? I live in Missouri and recently purchased around 30 acres from an older gentlemen who provided a copy of the survey he had done . The property bordered National Forest on two sides marked with good landmarks . I had trouble purchasing it from the start being 10 acres that was landlocked first from differnet owner. I did this knowing the gamble of getting stuck with it but the old gentleman told me not worry about the ten bordering his 20 acres that there was no access .I did not want chance a lawsuit later over easement crossing me . The old man then backed out selling the 20 ,but after more talks money talks 5,000 more he was ready to sell. I got a letter from the neighbor later informing me the fence the old man had built was on there property. They had never even mentioned when I had spoke with them before. The were also claiming he had done the fence a few years back while they were on vacation. The new survey showed a 16.5 by 43 strip encroachment that was intended for a road to the land originaly . The deeds show that but a deed of correction later took the road away and were not understood by the another Land owner who has called me recently and a surveyer said he still owns the 16.5 strip of land I just paid 750.00 for with agreement I would remove fence in question when the deed was complete . The neighbors then stole the fence and offered to it back . I turned it over to the Sherrif after securing the purchase of the 16.5 strip to highway . He said prosecuter said it is cival matter not criminal. I think was just wrong I my end of bargain even when they the neighbor moved a survey pin on the 16.5 line My question who do I sue first The old gentleman for selling something he did not own or the neighbors for stealing the fence.