“The man was questioned over the course of the evening and morning. During interrogations he has given satisfactory explanations and he is no longer a suspect,” said prosecutor Mikael Lundquist in a statement.
The Luleå District Court in northern Sweden, where the trial was set to begin Thursday, was evacuated after a bomb threat, which was called in via telephone shortly after 3pm.
The person who made the call told the receptionist that a bomb would go off at 4pm, according to the local Norbottens Kuriren newspaper.
Police immediately cordoned off the area, blocking off nearby roads and stopping local traffic, but were unable to find any traces of explosives in the area.
At about the same time as the building was evacuated, police arrested the witness near the court hall.
The victim, Esa Rano, was already known in Sweden after miraculously surviving a gruesome axe attack to the face and neck in 2008.
The attack was triggered by a village feud and left him permanently disfigured despite multiple surgeries.