Police say former Red Army Faction members are behind several robberies in Germany. (German federal police)

They used to be among Germany's most wanted: When Ernst-Volker Wilhelm Staub, Burkhard Garweg and Daniela Klette disappeared in the 1980s, West German authorities considered them to be extremely dangerous.

German authorities say all three belonged to the Red Army Faction (RAF), an extremist group that had killed politicians and businessmen throughout the preceding two decades. Also known as the Baader-Meinhof Gang, its members killed 34 people in kidnappings, bombings or assassinations between the early 1970s and 1998. Among them was Alfred Herrhausen, at that time the chairman of Deutsche Bank.

German police lost track of Staub, Garweg and Klette in the 1980s. In 1998, the RAF stopped its activities, when its members realized that their attempts to change German society had failed. Some members were convicted, others were never caught.

But the search for remaining ex-terrorists resumed last year, when authorities discovered the fingerprints of Staub, Garweg and Klette during an investigation of failed attempts to rob a money transporter. Now, there is another lead: Police say the three may be responsible for a series of supermarket robberies — carrying at least one anti-tank rocket launcher with them as their weapon.

How did some of Germany's scariest far-left extremists turn into robbers?

German police have speculated that the former RAF members could be in a dire financial situation more than two decades after their disappearance.

In Italy, the highest appeals court decided at the beginning of May that stealing smaller amounts of food might not constitute a crime, if  the alleged offender could prove the "immediate and essential need for nourishment," according to the BBC.

But the three cannot hope for similar leniency among German judges.

Officials say they are responsible for the robberies and that the gang might already have stolen as much as $420,000.

Staub, Garweg and Klette are believed to live in the neighboring Netherlands from where they allegedly plan their attacks on German targets. Although the trio is reported to be heavily armed, German media outlets have mostly reacted with mockery. "Ambush attack out of the revolutionary retirement," Germany's Der Spiegel news magazine commented.

Already in 1999, Klette and Staub were believed to have stolen approximately half a million dollars from an armored car. But shared among the three, that money amounted to a monthly allotment of less than $800. Investigators now believe that they spent their funds too quickly or thought they deserved better — forcing them to plan more risky robberies elsewhere in Germany.

Experts agree that most terror groups stop operating after a certain amount of time — organizations such as the Irish Republican Army (IRA) that are active over many decades are the rare exceptions.  Law enforcement agencies in Germany still struggle with many of the murders that were blamed on the RAF.

The murder of the Deutsche Bank's Herrhausen, for instance, is considered a closed but unsolved case. Until today, dozens of slayings remains unresolved, and several extremists believed to be involved in the deaths were never arrested, let alone convicted.

German authorities hope that the series of supermarket robberies could soon change that.

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