Shell’s oil supply chain in Germany has been damaged by a cyber-attack on a German oil storage and logistics firm, and the supermajor said on Tuesday that it is rerouting supplies to alternate depots.

Shell was able to “reroute to alternative supply depots for the time being,” a spokesperson for Shell’s German unit, Shell Deutschland GmbH, said in a statement. Oil supply and logistics firm Oiltanking Deutschland GmbH and oil trading firm Mabanaft, both subsidiaries of Hamburg-based group Marquard & Bahls, were both victims of a cyberattack affecting their IT systems a few days ago.

The companies detected the cyber intrusion on Saturday and initiated an investigation with the support of outside experts, according to an emailed statement obtained by The Associated Press from Oiltanking Deutschland and Mabanaft.

Although the Oiltanking GmbH Group continues to operate all terminals in all global markets, Oiltanking Deutschland GmbH’s German operations were “operating with limited capacity.”

The companies are attempting to resume normal operations as soon as possible however, the oil logistics and supply chain in Germany has been impacted, particularly oil logistics at supermajor Shell’s local operations.

According to the German business daily Handelsblatt, all of Oiltanking Deutschland’s loading and unloading tank systems in Germany have been halted.

Oiltanking Deutschland is one of the largest independent providers of tank space for oils, chemicals, and gases worldwide, according to Handelsblatt. Oiltanking Deutschland has 11 tank farm locations in Germany.

The German unit of Mabanaft “has also declared force majeure for the majority of its inland supply activities in Germany,” the AP cited a statement from the firm. Mabanaft is a gasoline, diesel fuel, jet fuel, heating oil, and other petroleum products importer, wholesaler, and supplier.