Multipoint observations on ground-based stations and a fleet of ISTP satellites allowed us to study the plasma processes in different regions of space for multiple (4) substorm event on December 22-23, 1996 which was characterized by almost constant solar wind pressure ∼ 1.2 nPa and southward IMF B_z. Comparison of measurements in the plasma sheet at opposite flanks showed (1) the similar loading/unloading processes in the tail, correlated with substorm development, and (2) a strong bursty convection concentrated in the narrow (Δy ∼ 15R_E) channel.