German police are set to probe the match against Bayern Munich and Schalke after a fraud complaint was filed against Bundesliga referee Marco Fritz.

"Police are now checking the circumstances," authorities in the city of Gelsenkirchen, Schalke's stomping grounds, said on Tuesday.

Schalke lost to the current German champions 3-0  this Saturday at home. All three goals were scored by Bayern's Polish-born striker Robert Lewandowski, one of them from a penalty kick.

However, Schalke fans were enraged by referee Fritz refusing two penalty appeals for the home team, both of them after apparent handballs from Bayern players.

Schalke: 'We know witnesses'

On Tuesday, Gelsenkirchen police said they had received the complaint from an unnamed a "Schalke supporter," targeting both Fritz and the video assistant Bastian Dankert, who could have advised Fritz to alter his decisions based on video evidence.

"The police are obliged to follow up on the complaint," a police spokeswoman told the SID news agency. The matter would also be passed to the prosecutor's office.

In response, FC Schalke posted a tongue-in-cheek tweet that none of the club members were behind the complaint.

"We asked around internally: none of us did it, honest! Still, we would be very interested in the results of the investigation," the club said on Twitter.

"It might help that we know witnesses who were at the crime scene when it happened," they added.

Read more:  Bundesliga Bulletin: Dortmund stay perfect, Lewandowski grabs hat trick

Tissues from police

Police also joked about the matter online when another user asked if he could contact the police about other football matches.

"You can always contact us," the officers said. "We can also provide tissues if your tears haven't run dry yet."

While prosecutors said they would look into the complaint, as they're obliged to in almost every instance, it remains unlikely that it leads lead to a full-on criminal investigation.

Saturday's match was Bayern Munich's first league victory of the season. Bayern have been Bundesliga league champions for the last seven years running.

Read more:  Opinion: Bayern Munich need to reach Robert Lewandowski's level

dj/msh (dpa, SID)

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