BERLIN (AP) — Police say they have arrested four men suspected of illegally procuring weapons ahead of festivities marking the anniversary of German reunification.

Cologne police spokesman Carsten Moellers says three of the men were arrested Saturday in the Bonn area and the fourth in Offenbach, near Frankfurt.

Moellers said Sunday that the men were arrested because "we couldn’t rule out that a crime was to be prepared" with the firearms they allegedly procured and in view of the upcoming reunification festivities.

Bonn, the former German capital, on Monday hosts events marking the 21st anniversary of reunification.