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We report the discovery of the Narrow-Line Seyfert 1 galaxy Mkn 335 in anextremely low X-ray state. A comparison of Swift observations obtained in Mayand June/July 2007 with all previous X-ray observations between 1971 to 2006show the AGN to have diminished in flux by a factor of more than 30, the lowestX-ray flux Mkn 335 has ever been observed in. The Swift observations show anextremely hard X-ray spectrum at energies above 2 keV. Possible interpretationsinclude partial covering absorption or X-ray reflection from the disk. In thisletter we consider the partial covering interpretation. The Swift observationscan be well fit by a strong partial covering absorber with varying absorptioncolumn density N_H= 1-4 x 10^{23} cm-2 and a covering fraction f_c=0.9 - 1.When corrected for intrinsic absorption, the X-ray flux of Mkn 335 varies byonly factors of 4-6. In the UV Mkn 335 shows variability in the order of 0.2mag. We discuss the similarity of Mkn 335 with the highly variable NLS1WPVS007, and speculate about a possible link between NLS1 galaxies andbroad-absorption line quasars.

Discovery of the Narrow-Line Seyfert 1 galaxy Mkn 335 in an historical low X-ray flux state