The German Football Association (DFB) has confirmed to ESPN FC it has opened an investigation against FC Magdeburg and Borussia Dortmund for setting off fireworks at Tuesday's DFB Pokal match.
During the tifo display, Magdeburg supporters also set off two flares in the stands, with visiting Dortmund fans doing similar in the away end ahead of the second half, and both sides could now face punishment.
On Wednesday, the DFB confirmed to ESPN FC that it is set to investigate the incidents, and will first ask both clubs for statements. The control body of the DFB will then decide about possible punishments for the two clubs.
With Dortmund playing under a suspended ban for away games until May 2018 following events at the DFB Pokal final in May, they could face an away match without any of their fans.
In the DFB's verdict regarding the cup final issued in July, it also threatened Dortmund fans with a ban on all tifos for one season.
"But right now all of that is speculation," a DFB spokesperson told ESPN FC in a written statement.
Earlier this season, amid a row between fans and the DFB, its president Reinhard Grindel said he wanted the governing body to abolish collective punishments such as partial stadium closures for the time being -- preferring to open dialogue with supporters -- as he felt it was unfair to penalise innocent fans for the actions of others.