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We study an interacting system of chemotactic species in two-space dimensions. First, we show that there is a parameter region which ensures simultaneous blowup also for non-radially symmetric solutions. If the existence time of the solution is finite, there is a formation of collapse (possibly degenerate) for each component, total mass quantization, and formation of subcollapses. For radially symmetric solutions we can rigorously prove that the collapse concentrates mass on one component if the total masses of the other components are relatively small. Several related results are also shown.