SAN ANTONIO (Reuters) - Authorities discovered marijuana, heroin and a loaded gun on Grammy-winning rapper Nelly's tour bus during a routine stop at a Border Patrol checkpoint in West Texas, law enforcement officials said on Thursday. A member of the singer's entourage took responsibility for the items and was arrested after the search on Wednesday evening, while others on the bus including Nelly were released, officials said. The checkpoint, which is not on the border, is used by the Border Patrol to check the citizenship status of motorists on Interstate 10. ...