GCN Circular 33528
N. Pankov (HSE), E. Klunko (ISTP), A. Pozanenko (IKI), S. Belkin (IKI) report on behalf of GRB IKI FuN: We observed the field of Swift GRB 230328B (Gropp et al. GCN 33527) with AZT-33IK telescope of Mondy observatory in R-filter on 2023-03-28 starting (UT) 15:27:18. We clearly detect the optical afterglow of GRB 230328B (Gropp et al. GCN 33527) at the position of (J2000) 19 24 01.828 +80 00 34.53 with an error of 0.5 arcsec in both coordinates, which coincides with the position of UVOT (Gropp et al. GCN 33527). Preliminary photometry of a stack of the first 5 images is following Date UT start t-T0 Exp. Filter OT Err. UL(3sigma) (mid, days) (s) 2023-03-28 15:27:18 0.026047 5*60 R 18.9 0.2 21.1 The photometry is based on nearby USNO-B1.0 stars.