By Alex MacDonald and Nicole Lundeen

Steelmakers ArcelorMittal (MT) and Voestalpine AG (VOE.VI) confirmed Thursday that their offices were searched by the German Federal Cartel Office due to alleged violation of antitrust law regarding steel deliveries to the German automotive industry.

The Federal Cartel Office said last month that it had searched the premises of three companies in the steel industry at four locations in the German states of Baden-Wuerttemberg, Bavaria and North Rhine-Westphalia. The probe was carried out by 19 cartel office officials, supported by local law enforcement officials and included the Duisburg office of Germany's largest steelmaker ThyssenKrupp AG (TKA.XE).

ArcelorMittal, Europe's largest steelmaker, said it has "a strong compliance policy and we are co-operating with the relevant authorities." The company declined further comment.

A spokesman for Austria-based specialty steelmaker Voestalpine said the company's sales office in Munich had been searched. He added in an emailed statement that Voestalpine supports the investigation by the cartel office.

ThyssenKrupp last July was fined 103 million euros ($132.94 million) by the German cartel office for its involvement in a rail pricing cartel. It is also likely that Thyssen will be sued for damages by its customers, including German railway operator Deutsche Bahn AG, which has previously confirmed it will seek damages.

--Monica Houston-Waesch and Jan Hromadko contributed to this story.

Write to Alex MacDonald at alex.macdonald@dowjones.com and Nicole Lundeen at nicole.lundeen@dowjones.com

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