We report the first radio interferometric search at 843 MHz for fast transients, particularly Fast Radio Bursts (FRBs). The recently recommissioned Swinburne University of Technology's digital backend for the Molonglo Observatory Synthesis Telescope array (the UTMOST) with its large collecting area (18 000 m^2) and wide instantaneous field of view (7.80 deg^2) is expected to be an efficient tool to detect FRBs. As an interferometer it will be capable of discerning whether the FRBs are truly a celestial population. We show that UTMOST at full design sensitivity can detect an event approximately every few days. We report on two preliminary FRB surveys at about 7 per cent and 14 per cent, respectively, of the array's final sensitivity. Several pulsars have been detected via single pulses and no FRBs were discovered with pulse widths (W), in the range 655.36 μs −3.2