Abstract The EPR-type strangeness correlation in the K0 K 0 system produced in the reaction p p → K 0 K 0 at rest has been tested using the CPLEAR detector. The strangeness was tagged via strong interaction with absorbers away from the creation point. The results are consistent with the QM non-separability of the wave function and exclude a spontaneous wave-function factorisation at creation (CL >99.99%).