Two sophisticated drug-smuggling tunnels outfitted with lighting and ventilation systems have been discovered along the US-Mexico border.

Hooded gunmen killed the mayor of a small town in the northern Mexico state of San Luis Potosi, and prosecutors announced the arrest of seven suspects in the massacre of 72 migrants in August.

Argentina’s interim president Adolfo Rodriguez Saa has resigned after a volatile week in office, saying his support collapsed within his Peronist party as he tried to surmount a deep economic crisis.

Argentina's interim president says he will suspend the country's foreign debt payment.

Last-minute political wrangling delayed the Argentine Congress from appointing an interim president last night as legislators argued over how long a caretaker should remain in office and when to call new elections.