CALEXICO – Surveillance video of a deadly shooting last month of a would-be illegal migrant by a Border Patrol agent is prompting calls by the Mexican government for an investigation, although it shows the agent apparently firing in self-defense. A Border Patrol video of that incident, derived from those surveillance images and originally meant as an internal report to Border Patrol headquarters in Washington, has since been leaked onto the Internet. Ramiro Gamez Acosta, 20, was shot once in the chest by an agent armed with an M-4 carbine last March 26. He died within minutes.