  The Mini-EUSO telescope is the first space-based detector of the JEM-EUSO
program. It was launched for the International Space Station on August
22$^{nd}$, 2019 to observe from the ISS orbit ($\sim$420 km altitude) various
phenomena occurring in the Earth's atmosphere through a UV-transparent window
located in the Russian Zvezda Module. The dimension of the window defines and
constrains the dimension of the optics, based on a set of two Fresnel lenses of
25 cm diameter each, almost two orders of magnitude smaller than the system
foreseen for a larger space-based detector, like the original JEM-EUSO detector
or the future POEMMA. As a consequence, the energy threshold of Mini-EUSO is
very high, above $10^{21} $eV. Nevertheless, a series of events that resemble
the shape and the time duration of EAS-induced events have been detected in
Mini-EUSO data. This contribution presents the most interesting cases, showing
that the vast majority of the EAS-like events can be traced back to ground
sources repeatedly flashing and triggered many times by Mini-EUSO. Some
non-repeated EAS-like events are also present. In these cases, it is possible
to exclude their cosmic origin through the comparison with simulated events.
Since it is clear that those events can not be originated by a UHECR, we
decided to rename them "Short Light Transients" or SLTs. Finally, it was
possible to associate some of the SLTs with atmospheric activity. This analysis
confirms the validity of the JEM-EUSO detection principle and shows that it is
possible for a space-based detector to distinguish between events induced by
UHECRs and events with a different origin.
