HeidelbergCement AG, Germany’s biggest cement maker, said a joint venture was raided by German antitrust officers who are investigating price fixing in the erection of silos on building sites. The cartel authorities searched offices of Franken Maxit Mauermoertel GmbH, a venture between HeidelbergCement and a private investor that’s based in the south-German town of Kasendorf, spokeswoman Brigitte Fickel said today. The raid took place “several weeks ago,’” she said.

German authorities are investigating whether an unspecified number of cement producers fixed prices for the installation on construction sites of silos used to store cement prior to mixing, Irene Sewczyk, a spokeswoman for the cartel office said. She said offices were searched at the end of May, declining to identify the companies concerned. Spokespeople for Dyckerhoff AG, Germany’s second-biggest cement maker weren’t immediately available to comment.

The raids aren’t related to a prior investigation into six cement makers by the country’s Federal Cartel Office in 2003, which resulted in a damages lawsuit that’s still going through the German courts.