Police on Tuesday arrested the alleged leader of a gang that stole US$70 million (euro57 million) from a Brazilian bank two years ago in what was then the world's biggest heist.

Jossivam Alves dos Santos was detained in the capital of Brasilia, federal police spokesman Lincoln Fructoso Siqueira said.

Police said Santos led the 2006 robbery in the northern city of Fortaleza, where thieves tunneled 260 feet (80 meters) to reach the vault of a Brazilian bank.

The gang used shovels, pickaxes, saws and drills to dig and cut through the vault's steel-reinforced concrete floor, some 3.6 feet (1.1 meters) thick. They also created a pulley system with a plastic barrel to transport the money through the tunnel.

Eleven suspects have already been convicted, but less than US$10 million (euro6.7 million) has been recovered and police believe others may still be at large.

A few months after the robbery, the suspected mastermind, Luis Fernando Ribeiro, was kidnapped and murdered even though his family paid a ransom of nearly US$1 million (euro670,000 million). Another suspect was found killed on a remote ranch.

It was the world's biggest robbery until more than US$90 million (euro60 million) was stolen from a London security warehouse last year.