BERLIN — A German court in the city of Düsseldorf sentenced a Tunisian national on Thursday to a 10-year prison term for planning a biological terror attack that could have murdered as many as 13,500 people.The 31-year-old jihadi Sief Allah H. planned the mass murder with his wife, the 41-year-old German Yasmin. The presiding judge Jan van Lessen said that the couple "wanted to create a climate of fear and uncertainty among the German population.” According to the court statement, the couple started in September 2017 to organize a “jihadi motivated explosive attack in Germany” with the use of the “deadly poison ricin.”Sief Allah H. supported the Islamic State and ordered castor seeds and metal ball bearings via the internet to construct the biological weapon.The goal of the explosion, according to the court statement, was to murder “other believers” who don’t embrace Islam. Judge van Lessen noted that Allah H. made two attempts join the Islamic State as a combatant in Syria.The authorities confiscated the components of a planned biological weapon in the apartment of the couple in Cologne-Chorweiler. According to the court, “They show that the accused were well advanced in the manufacture of an explosive device and had already made a significant amount of the ricin toxin from the castor beans they had ordered online.”The court said that”Radical Islamic content had been found on their mobile phones, demonstrating their radicalization and the decision to commit a terrorist attack based on it. The planned attack would most likely have resulted in numerous fatalities and injuries. The attack was prevented by police access on June 12, 2017.”German media reports said the biological weapon could have killed as many as 13,500 people.Allah H. appealed his sentence. The trial against his wife is set to continue, with the next court hearing slated for April 1.