[en] The results of a search for new particle production with decay modes which include neutral strange particles and muons are reported. The number of neutral strange particles produced by interactions of a 225-MeV pion beam on a nuclear target was measured when muons were and were not required in the final states. It was concluded that one does not produce neutral strange particles which are correlated with muons at an observable cross section greater than 1 nb in the 2μ . E trigger. This result can be used to place limits on charmed particle production