Police in the Mississippi River city of Alton say a body found in an abandoned home's basement was that of a 66-year-old man.

The (Alton) Telegraph reports Larry Arnold of Alton was found dead Tuesday by workers for a Missouri demolition company.

Madison County Coroner Steve Nonn says an autopsy has been completed. But investigators are awaiting results of toxicology tests that they hope will pinpoint why Arnold died.

The coroner says, at least for now, Arnold appears to have died of natural causes.

It remains unclear how long the body had been there.

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