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Analysis of seismic swarms, their laboratory modeling and computer simulation allows to clarify some features of swarm activity and physical mechanisms controlling seismicity dynamics. Seismic swarms in Corinth rift of 2001 and 2003-2004 years were studied on the base of catalogue of Corinth Rift Laboratory. Typical properties of swarm activity dynamics are revealed. GR b-value decreases and fractal dimension of hypocenter set (d-value) increases on the stage of swarm activation. Variations of these parameters are contrary on the stage of swarm relaxation. Laboratory modeling of seismic swarms was carried out with lever press and artificial models. Small water box was placed on the upper surface of concrete specimen step-loaded uniaxially under the biaxial compression. Water infusion into a sample caused complicated activation of the failure process. As a result of water diffusion the area closest to the water box with rather small level of Coulomb stress becomes more active at first. Further AE activation arises in the area of the largest Coulomb stress led to formation of a macrocrack. It was found that the structure of AE after water infusion is qualitatively similar to the same for earthquake’s swarms.