But wherever he ends up in United States, Guzman is certain to cause a media frenzy and present a security challenge that has bedeviled Mexican authorities. Last year, the boss of the cutthroat Sinaloa cartel escaped prison for a second time — using a mile-long tunnel and allegedly with help from crooked guards — and spent several months on the run before being recaptured in January after a bloody shootout in the coastal city of Los Mochis.