State prosecutors said on Tuesday that though the two men had discussed attack plans, there was not enough evidence to support authorities' initial suspicion that the men were “preparing a serious crime against the state”.
The Nigerian and Algerian citizens - both in their 20s and born in Germany - were arrested on February 9th in a police raid in the Lower Saxon university town, as well as in Hesse, that involved 450 officers at around a dozen buildings.
At the time, Göttingen's police chief Uwe Lührig said that they had gained knowledge of a possible concrete and imminent attack, and therefore a quick police operation was necessary.
“We had, in my assessment, absolutely no other option,” Lührig said.
But according to prosecutors on Tuesday, while the men had in fact discussed preliminary ideas for an attack, they “had not committed any concrete crime”. And therefore the conditions for launching a further criminal investigation or issuing an arrest warrant were not met.
“They discussed what someone could do, and several possibilities were considered as well as rejected,” said Celle prosecutor's office spokesperson Bernd Kolkmeier.
The two men are currently in custody pending deportation, where they can be held for up to 12 months. According to Spiegel, the two may still be deported as decided by security authorities because the aversion of potential danger is top priority.
During the searches police discovered reconstructed weapons with large amounts of ammunition, as well as Isis flags.
Both men have reportedly lived for a long time with their families in Göttingen, and had also been known members of the radical Islamist scene.
Unconfirmed DPA information claimed that the men had discussed killing police officers.