Police moved in on the Syrian suspect yesterday and he has been accused of planning a bomb attack by federal prosecutors.
The 19-year-old was allegedly plotting an Islamist-motivated attack before his arrest.
Interior Minister Thomas de Maiziere praised the police for averting a “major terrorist attack”.
The man was identified only as Yamen A. by the prosecutor’s office spokeswoman.
A prosecutor’s office statement said: “According to the findings so far, Yamen A. made the decision no later than July 2017 to detonate an explosive device in Germany in order to kill and injure as many people as possible.”
“As a result, he began to procure components and chemicals needed to make an explosive device.
“Whether the suspect had already envisaged a specific target for his bomb attack is still unclear.”
It was also claimed that Yamen A. contacted jihadis online and described himself as a “soldier of the caliphate”.
The arrest took place during the early hours of Tuesday morning in the northeastern town of Schwerin.
The home of the suspect and others not thought to have been directly involved were searched by police.
Chemicals that could be used to create an explosive known as TATP were ordered online and two radios, batteries and mobile phones were also acquired by the suspect, the spokeswoman claimed.
There is currently no indication that he was a member of a terrorist group.
De Maiziere said the suspect was arrested “late enough to secure evidence and at the same time early enough to reliably ward off the danger”.
He said: “The threat situation in Germany remains high. Germany, Europe, the West are in the sights of Islamist terrorism.”