BERLIN (Reuters) - Deutsche Bahn is reviewing consultancy contracts granted to former managers without the knowledge of the state-owned railway operator’s supervisory board, it said on Thursday.

FILE PHOTO: A locomotive engine of German railway Deutsche Bahn is seen at the main train station in Frankfurt, Germany, March 27, 2019. REUTERS/Kai Pfaffenbach/File Photo

The German firm was auditing more than 20 contracts awarded to the former managers between 2010 and 2018, sources earlier told Reuters before the company confirmed the report.

Supervisory board chairman Michael Odenwald told Reuters he was determined to uncover what had happened.

“I will make sure that the matter is fully cleared irrespective of the people involved,” Odenwald said.

The issue may add to pressure on Deutsche Bahn, which is facing public complaints about poor service and delays.

The sources had said that, in some cases, former managers were granted consultancy contracts after leaving the firm but did not do any work for Deutsche Bahn.

The value of the contracts ran into millions of euros, the sources said, although they did not give any specific figures.

Deutsche Bahn said in a statement its supervisory board would convene in coming weeks to discuss “irregularities”.

The company said it had appointed a law firm to review the findings of an internal investigation into the granting of contracts to former executives.

Germany’s Federal Audit Office said it was aware of the case. “We are in the process of conducting an audit related to the issue,” a spokesman said, declining to give more details.

In addition to dealing with public complaints about service quality, Deutsche Bahn also faces a debt mountain of 20 billion euros ($22.5 billion), while its financing deficit is expected to hit 5 billion euros by 2023.