BERLIN (AP) — German investigators say they have shut down a data processing center installed in a former NATO bunker that hosted sites dealing in drugs and other illegal activities. Seven people were arrested.

Officials said Friday that the former military bunker in Traben-Trarbach, a picturesque town on the Mosel River in western Germany, was acquired in 2013 by a Dutch man who turned it into a heavily secured data processing center.

Prosecutor Juergen Bauer said 13 people are under investigation, including three Germans and seven Dutch citizens.

Seven were arrested in raids Thursday. They are suspected of membership in a criminal organization because of a tax offense, as well as being accessories to hundreds of thousands of offenses involving drugs, counterfeit money, forged documents and the distribution of child pornography.