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Weak first-order phase transitions from axial to oblique spin ordering in FeBr2 are evidenced by superconducting quantum interference device magnetometry in axial fields H1(T) above the multicritical point, Hm=2.4 MA/m, Tm=4.6 K, and below the antiferro-to-paramagnetic phase line, Hc (T), in agreement with recent specific-heat data [H. Aruga Katori, K. Katsumata, and M. Katori, Phys. Rev. B 54, R9620 (1996)]. The ordering of the in-plane moments is probably due to nondiagonal coupling to the longitudinal ones, both of which increase discontinuously at H1 (T) only under an additional symmetry-breaking transverse field.