TITLE: GCN CIRCULAR NUMBER: 21390 SUBJECT: IBAS weak Alert nr.7881: possible GRB 170730A DATE: 17/07/30 07:45:59 GMT FROM: Diego Gotz at CEA D.Gotz (CEA Saclay) on behalf of the IBAS Localization Team reports: the weak IBAS Alert nr. 7881 corresponds to a weak transient source lasting about 100 s, starting at 00:09:32 UT on July 30th 2017, localized at R.A: 245.3407 deg Dec: -60.8832 deg with an unceratinty of 2.5 arc min (90% c.l.). We prliminarly classify it as a GRB, but we cannot exclude that it is a new Galactic source due to its low Galactic latitude. Futher analysis is on-going. This message can be cited.