TITLE: GCN CIRCULAR NUMBER: 23398 SUBJECT: IceCube-181031A retraction DATE: 18/10/31 02:44:01 GMT FROM: Erik Blaufuss at U. Maryland/IceCube The IceCube Collaboration (http://icecube.wisc.edu/) reports: On 18/10/31 at 02:02:51 UT IceCube issued an alert (https://gcn.gsfc.nasa.gov/notices_amon/66412090_131680.amon) reporting the detection of an event with a high chance of being of astrophysical origin. Upon further examination by the IceCube collaboration, the event was found to clearly *not* be of astrophysical origin. This event was a rare case of near-in-time coincident events allowing a clear background event to pass the contained event selections. We apologize for any confusion this error may have caused. The IceCube Neutrino Observatory is a cubic-kilometer neutrino detector operating at the geographic South Pole, Antarctica. The IceCube realtime  alert point of contact can be reached at roc@icecube.wisc.edu