Police in Sao Paulo have foiled the world’s biggest bank robbery after discovering a well constructed 500-metre tunnel, complete with lighting, ventilation and rail tracks, leading from a rented house to the vaults of the Bank of Brazil.The thieves hoped to steal up to £250 million, police said, and had planned to carry out the raid this weekend. Several bullet-proof cars, suspected of having been prepared as getaway vehicles, have been impounded as part of the police operation.

“This would have been the biggest bank robbery in the world,” chief investigator Fabio Pinheiro Lopes told the Guardian.

“They are an extremely dangerous and organised gang with a long history, including some violent crimes like homicide. If you look at their ages most are above 35 – well above the age of your average Brazilian criminal,” he added.

The gang are understood to have invested at least £750,000 to fund the construction of the tunnel and other logistics. Among the arrested is a woman who used a false name to rent the house where the tunnel began.

Suspicions were aroused when police in the run-down north of the city were alerted to the construction of an unusually luxurious house. It turned out to be the gang’s temporary headquarters. Undercover officers rented a neighbouring building and monitored communications and movements.

Police say the gang’s leader was Alceu Ceu Gomes Nogueira, 35. He is also suspected of having been involved in an attack on cash deposits in Paraguay in April, when nearly £10 million was stolen and a police officer was killed in a long gun battle. Sao Paulo police said that he had told them he worked as a farmer, and had no connection with the robbery.

Local media reported that Nogueira is heavily involved with a notorious gang called the PCC (First Command of the Capital). It is believed that Nogueira commanded a prison riot in 2006 at the behest of the PCC, the same year the gang mounted a series of bloody attacks which brought São Paulo to its knees.

Another alleged accomplice is Marcos Paulo Chini, 44. He was serving a jail sentence in the northern state of Maranhao after being convicted for his part in a bank robbery in 2015. In May this year he disappeared while he was temporarily released for a Mother’s Day visit.

Twelve of the other 14 people arrested have previous convictions, including murder, robbery, drug trafficking, and illegal possession of weapons.

The tunnel was high enough for a person to stand inside, and supported with metal and wooden beams. Rail tracks had been laid to transport the banknotes. Police said that they had also seized construction materials and workers’ clothes that were scattered throughout the area. Frozen food to provide for a large team of labourers was discovered.

Had the plot succeeded, it would have dwarfed Brazil’s previous biggest heist, when thieves made off with 3.5 tonnes of cash, worth £35 million, from a regional office of the Brazilian central bank in the city of Fortaleza in 2005. On that occasion, a tunnel was also built from a rented home near by. Police have yet to ascertain whether the two operations are connected.

Alceu Ceu Gomes Nogueira being led away by the Police

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