Bombs exploded at three banks in the Argentine capital today, including two branches of US giant Citibank, killing one security guard and injuring one other person, police said.
Federal police said the bombs were not big enough to cause major destruction to the buildings.
It was not clear who was responsible for the bombs. In addition to Citibank, an explosion hit Argentine bank Banco Galicia but no injuries were reported.
The last time Buenos Aires' banks were targeted by small bombs was during the August visit of International Monetary Fund Managing Director Mr Rodrigo Rato. No one was injured or killed in those blasts.
In the wake of Argentina's economic collapse in 2002, many Argentines blamed foreign banks for their country's woes.
Citigroup officials were not immediately available for comment.