What kind of people are we talking about here? Stereotypically, someone who chains a pit in the middle of an undeveloped lot won't waste a lot of time trying to figure out why it's suddenly laying there dead. The odds are great that the dog will starve to death so you might consider speeding up the process.
Havn't spoke to them in years. I was jogging one evening when I first moved in and and their teenage son yelled profanaties out the window as he drove by later I had words with the mother about it and havnt talked to them since. They do feed and water the dog everyday from what I can tell.