“If sufficient, concrete evidence of further perpetrators turn up, we will restart the investigation,” a spokesman for the federal prosecutor's office told the Süddeutsche Zeitung (SZ) on Monday.
The 1980 “Wiesn Attack” killed 13 people, among them the man who planted the bomb, 21-year-old Gundolf Köhler.
Now the victims' lawyer has petitioned for the case to be re-opened after he found a new witness to come forward.
SZ reported that prosecutors have questioned the woman and that she had named an accomplice in the crime.
Until recently, investigators believed that the bomber had acted alone, despite his ties to the far-right “Hoffmann military sports group”.
But the witness says she found flyers with an obituary of Köhler in the new suspect's locker before the bomber's name had been published.