Buenos Aires, London- A gang of over 50 armed members have stolen several million dollars from a vault in Paraguay. According to local officials, this operation was the “heist of the century.”

The German News Agency said police reported that the assailants are Brazilians who killed a police officer during the raid in Ciudad del Este, the South American country’s second-largest city.

The Paraguayan Interior Ministry said three robbers were killed hours later in a gunbattle with Brazilian police across the border. The ministry added that five members of the gang were arrested in Itaipulandia, 50 kilometers north of Ciudad del Este.

Initial estimates placed the stolen sum at around 40 million dollars, but a spokesman for Prosegur, the security company targeted in the raid, denied these reports.

The gangsters used explosives to gain access to the vault at a cash-storage facility in the Paraguayan border city, which is known for its criminal gang activity.

Security authorities thought that the involved armed members have escaped to Brazil by motorboat via the Parana River.

According to media reports, some of the stolen money was recovered.