New results from NA48 experiment on neutral kaon rare decays

Recent results by the NA48 collaboration on neutral kaons rare decays into the $\pi^{+}\pi^{-}e^{+}e^{-}$ final state are presented. A large CP-violating asymmetry $A(K_{L})=(13.9 \pm 2.7 \pm 2.0)$% has been observed in the $K_{L} \to \pi^{+}\pi^{-} e^{+}e^{-}$ decay. The $K_{S} \to \pi^{+}\pi^{-}e^{+}e^{-}$ decay has been observed for the first time, showing no such asymmetry.