KINGSTON, Mo. (AP) — A man charged with tampering with a vehicle used by two Wisconsin brothers who are missing and presumed dead in Missouri was involved in a business arrangement with another farmer that included calves owned by the brothers, according to people involved in the deal.

Brothers Nick and Justin Diemel, from Shawano County, Wisconsin, disappeared July 21 while visiting northwest Missouri for a trip related to their cattle business. Authorities say the brothers are presumed dead. Human remains found on a farm owned by Garland Nelson have not been identified.

The brothers disappea...