One of the most serious bank robberies happened in Brazil. In August 6, 2005, the thieves managed to steal about 65 million dollars from the central bank in Fortaleza.
To do that the criminals rented a house near the bank. Then they tunnelled a way which ended exactly under the bank vault. The way was 80 meters long and 70 centimeters in diameter. The police said it could take about 3 months for 1o people to finish it. After that the robbers broke the concrete floor, which was 1,5 meter high, and walked off with all the money.
Next day, on monday, the bank employees were shoked seeing an empty vault and the hole in the middle. The police thought that someone from the bank might help the criminals.
So far 11 suspects were arrested and only 10 million dollars were returned.