Following a brief review on this subject, we present the recent results of a hybrid-emulsion experiment at KEK (E373). One of the topics is the discovery of ⁶_ΛΛHe which consists of ΛΛppnn, named as Lambpha by Bando.

The binding energy was uniequly determined for the first time and indicate weakly attractive Λ-Λ interaction. We discuss the implication of this result in relation with the baryon-baryon interaction models, H-dibaryon and the possiblility of H-nuclei. Future experimental plans on this subject are also described to provide a future prospects on s=-2 nuclear physics.