It is more than a rumor. Eight or nine years ago I saw a Border Patrol internal memo that was given to all the agents, stating that the bounty was $20,000.00, several agents have told me that it has been raised to $200,000.00.
These incidents with the Federales crossing the border have been occuring for years, they have not been reported by the press, most incidents don't even make the news here near the border.