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Context: GRB 211106A and GRB 211227A are recent gamma-ray bursts (GRBs) withinitial X-ray positions suggesting associations with nearby galaxies (z < 0.7).Their prompt emission characteristics indicate GRB 211106A is a short-durationGRB and GRB 211227A is a short GRB with extended emission, likely originatingfrom compact binary mergers. However, classifying solely based on promptemission can be misleading. Aims: These short GRBs in the local Universe offeropportunities to search for associated kilonova (KN) emission and study hostgalaxy properties in detail. Methods: We conducted deep optical and NIRfollow-up using ESO-VLT FORS2, HAWK-I, and MUSE for GRB 211106A, and ESO-VLTFORS2 and X-Shooter for GRB 211227A, starting shortly after the X-ray afterglowdetection. We performed photometric analysis to look for afterglow and KNemissions associated with the bursts, along with host galaxy imaging andspectroscopy. Optical/NIR results were compared with Swift X-Ray Telescope(XRT) and other high-energy data. Results: For both GRBs we placed deep limitsto the optical/NIR afterglow and KN emission. Host galaxies were identified:GRB 211106A at photometric z = 0.64 and GRB 211227A at spectroscopic z = 0.228.Host galaxy properties aligned with typical short GRB hosts. We also comparedthe properties of the bursts with the S-BAT4 sample to further examined thenature of these events. Conclusions: Study of prompt and afterglow phases,along with host galaxy analysis, confirms GRB 211106A as a short GRB and GRB211227A as a short GRB with extended emission. The absence of optical/NIRcounterparts is likely due to local extinction for GRB 211106A and a faintkilonova for GRB 211227A.

A search for the afterglows, kilonovae, and host galaxies of two short GRBs: GRB 211106A and GRB 211227A