TITLE: GCN CIRCULAR NUMBER: 31675 SUBJECT: Tev Blazar as possible optical counterpart of the high-energy neutrino IceCube-220303A DATE: 22/03/04 07:46:26 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs K.Zhirkov behalf MASTER team MASTER-Net automatically inspected IceCube-220303A error box (Ttrigger=2022-03-03 18:00:07.62UT, Tnotice=2022-03-03 20:49:24UT). MASTER auto-detection system discovered Tev blazar 4C 09.57 (http://simbad.u-strasbg.fr/simbad/sim-id?Ident=0FGL%20J1751.5%2B0935%20 ) inside 3-sigma error-box in high stage state in 10 hours after the trigger time. The analysis will be continued. Additional observations are planned.