Cantonal police uncovered the arms on Thursday during the search of an apartment in Ramsei, part of the municipality of Lützelflüh.
The dawn raid occurred after a tenant of the apartment was arrested in connection with a narcotics case, according to a report from SDA, the Swiss news agency.
The man was released after questioning.
The regional prosecutor for the Bern-Mittelland region authorized the search, police said.
Details about the number and nature of the weapons seized have not been divulged, but authorities put extensive security measures into place after the search.
The village’s main road was closed.
Fire fighters from Lützelflüh and Bern arrived on the scene, in addition to personnel specialized in dealing with dangerous chemicals.
Explosives experts were called in to transport the weapons to a secure place.
Soldiers from the Swiss army also helped out.
The incident occurred in an unlikely location, a rural region known for its famous cheese.
Investigators are seeking more information in the case.