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We present a detailed analysis of the X‐ray spectrum of the Seyfert 2 galaxy NGC 454E, belonging to the interacting system NGC 454. Observations performed with  Suzaku ,  XMM–Newton  and  Swift  allowed us to detect a dramatic change in the curvature of the 2–10 keV spectrum, revealing a significant variation of the absorbing column density along the line of sight (from  ∼ 1 × 10 24   cm  −2   to  ∼ 1 × 10 23   cm  −2  ). Consequently, we propose this source as a new member of the class of ‘changing look’ active galactic nuclei (AGN), i.e. AGN that have been observed both in Compton thin (  N  H = 10 23   cm −2  ) and reflection‐dominated states (Compton thick,   N  H  &gt; 10 24   cm −2  ). Due to the quite long time lag (six months) between the  Suzaku  and  XMM–Newton  observations, we cannot infer the possible location of the obscuring material causing the observed variability. In the 6–7 keV range, the  XMM–Newton  observation also shows a clear signature of the presence of an ionized absorber. Since this feature is not detected during the  Suzaku  observation (despite its detectability), the simplest interpretation is that the ionized absorber is also variable; its location is estimated to be within  ∼ 10 −3   pc from the central black hole, probably much closer in than the rather neutral absorber.

NGC 454: unveiling a new ‘changing look’ active galactic nucleus