A 63-year-old known as "the Broomstick Robber" has been charged with attempting to extort €3 million in cash and diamonds from Bayern Munich, Munich police have confirmed.
During the 1990s, Harald Zirngibl robbed 16 banks in the Munich region and earned his nickname for his habit of shutting in his victims and locking the doors with a broomstick.
Zirngibl was arrested in November 1998 after having stolen an estimated total of €4.75m. He was sentenced to 10-and-a-half-years in prison, and released in 2009.
According to Suddeutsche Zeitung, Zirngibl tried several new professions upon his release from prison, which included selling hand-produced sex toys and writing books, with his autobiography, "I was the Broomstick Robber: My failed dream," published in 2011.
However, police have said that Zirngibl, who had been dubbed "Munich's friendliest bank robber" in the 1990s, tried to extort €3m in cash and diamonds from Bayern Munich earlier this month.
In the letter he is alleged to have sent to Bayern in February, he warned the Bundesliga club about potential "danger," making a vague reference to a drone over the car park at the Allianz Arena, and asked for €1m in cash, plus 1.1m Swiss Francs and diamonds, with the grand total adding up to €3m.
Bayern, unaware of the extortioner's identity, went to the police despite a warning not to involve the authorities.
A second letter was sent to the club asking for the money to be paid in a different denomination as the €500 note was being phased out in Germany. The extortioner then contacted the German champions through a SIM card supplied in one of the letters.
Two days later, police were convinced that Zirngibl was behind the extortion as he tried to get closer to the money by texting the club and sending them on a "paper chase" through rural Bayern, Munich detective Stefan Kastner said in Suddeutsche Zeitung.
Four days later, Zirngibl was arrested in Mainburg, some 50 kilometres outside of Munich.
"He immediately confessed to the extortion attempt," Kastner added in Bild.
FC Bayern Munich have not commented on the incident.