... ultimately proved unsustainable. To finance the trade gap, Mexico City had become increasingly reliant on volatile portfolio investment. A series of political shocks in 1994 - an uprising in the southern state of Chiapas, the assassination of a presidential candidate, several high profile kidnappings, the killing of a second high-level political figure, and renewed threats from the Chiapas rebels - combined with rising international interest rates and concerns of a devaluation to undermine investor confidence and prompt massive outflows ... — The 1995 CIA World Factbook • United States Central Intelligence Agency