A Tunisian man faces prosecution for planning an Islamist terrorist attack via a rare and highly dangerous poison, a plot thwarted by investigators in Germany this week. The alleged perpetrator had begun buying precursors to the deadly chemical ricin and had succeeded in manufacturing a significant quantity before police raided his apartment on Tuesday:

A 29-year-old man is suspected of planning an Islamic extremist plot to carry out an attack in Germany using the deadly toxin ricin, which was thwarted by authorities who raided his Cologne apartment, federal prosecutors said Thursday.

Sief Allah H., a Tunisian whose last name wasn’t given in line with German privacy laws, was taken into custody Tuesday during the raid on his apartment, and formally arrested Wednesday after a judge reviewed the evidence.

Authorities are still investigating exactly how the suspect planned to use the toxin, but said he was working on a “biological weapon” attack in Germany.

“We don’t know how, or how widely, the ricin was to have been distributed,” said prosecutors’ spokesman Markus Schmitt.

Or whether it had already been distributed, for that matter, although it would become rapidly apparent if he had. Those with long memories might remember how ricin was used by the Soviet bloc in the latter part of the Cold War. In 1978, Bulgarian dissident Georgi Markov got killed by an umbrella jab to the leg in London that planted a ricin-laced pellet into his body, causing his death within a few days and creating an international storm of controversy. Another Bulgarian dissident, Vladimir Kostov, managed to survive an assassination attempt in Paris from an identical ricin pellet. The Soviet Union was known to have produced weaponized ricin and were widely suspected of being behind both attacks.

The US has had some experience with ricin attacks too, although entirely from kooks. Actress Shannon Richardson is doing an 18-year stretch for sending a letter containing ricin to Barack Obama during his presidency as part of a lunatic plot to frame her estranged husband. Other letter attacks have taken place as well, one of which was aimed at Michael Bloomberg. It’s accessible enough to make one wonder why it hasn’t been used more often, especially by organized groups such as ISIS and al-Qaeda.

Perhaps this case’s conclusion might give a little insight into that question. It’s not easy to gather the necessary materials clandestinely, and it seems likely that the perp’s purchases of large quantities of castor beans sent up a red flag somewhere. Authorities hinted at that in their statement to the court:

He is accused of having started procuring material, including a large quantity of seeds needed for the creation of ricin, online in mid-May.

The suspect succeeded in creating the toxin this month and investigators found it during a search of his Cologne apartment, the statement said.

The Soviets made it work because they had the power of the state behind their efforts. Non-state actors have more obstacles to clear. That again calls into question exactly what this person had planned, and who else was involved in the plot. There are easier poisons to acquire than ricin, although none as deadly. The objective had to be significant for that kind of risk. We’re fortunate that no one found out the hard way what this perp and/or cell had in mind.