  Bismuth, the heaviest of all group V elements with strong spin-orbit
coupling, is famously known to exhibit many interesting transport properties,
and effects such as Shubnikov-de Haas and de Haas-van Alphen were first
revealed in its bulk form. However, the transport properties have not yet been
fully explored experimentally in thin bismuth nor in its 2D limit. In this
work, bismuth flakes with average thicknesses ranging from 29 to 69 nm were
mechanically exfoliated by a micro-trench technique and were used to fabricate
four-point devices. Due to mixing of components, Onsager's relations were used
to extract the longitudinal ($R_{xx}$) and Hall ($R_{xy}$) resistances where
the latter shows a Hall anomaly that is consistent with the Anomalous Hall
Effect (AHE). Our work strongly suggests that that there could be a hidden
mechanism for time-reversal symmetry breaking in pure bismuth thin films.
