In this Letter, the surname of author Benny Trakhtenbrot was misspelled ‘Trakthenbrot’. The affiliation for author Sylvain Veilleux should have been ‘Department of Astronomy and Joint Space-Science Institute, University of Maryland, College Park, MD, USA’ instead of ‘Instituto de Astrofísica…Chile’. In addition, we omitted to cite a reference1 by a co-author in the Abstract sentence ‘Recent observations have shown that a black hole is likely to become heavily obscured behind merger-driven gas and dust,….’. This has been added to the reference list as ref. 9 of the original Letter, with subsequent references renumbered accordingly. Finally, the following sentence has been added to the Acknowledgements section ‘We appreciate the help of R. M. McGurk with the initial night of Keck telescope observations and initial data reductions.’ This Letter has been corrected online.