DUESSELDORF, Germany (Reuters) - German prosecutors said on Tuesday they had found no grounds to investigate Brenntag, the world’s largest chemicals distributor, over the sale to a company in Syria of substances that can be used in chemical weapons.

Sueddeutsche Zeitung, working with other media outlets, had in June reported that Brenntag sold ingredients with potential dual use in painkillers and nerve gas to a Syrian drugmaker, hitting its shares on concern over political repercussions in the United States.

But the prosecutors office in the western city of Duisburg said there were no sufficient signs of wrongdoing that would justify an investigation into Brenntag.

Duisburg prosecutors had taken over the case from counterparts in Essen, who in June received the initial complaint about Brenntag from three non-governmental organisations: New York’s Open Society Justice Initiative, Berlin’s Syrian Archive and Switzerland’s Trial International.

Brenntag said in June that a Swiss subsidiary had in 2014 supplied diethylamine and isopropanol to Syrian drugmaker Mediterranean Pharmaceutical Industries (MPI) to produce a pain killer, in line with relevant laws and regulations.

Swiss drugmaker Novartis said it had granted MPI contract manufacturing and local distribution rights for pain relief skin gel Voltaren.

The U.N. Commission of Inquiry on Syria said in March that government forces had perpetrated 32 of 37 chemical attacks it had reported during the Syrian war. The government denies using chemical weapons.