  Two new excited states, $\Omega_c(3185)^0$ and $\Omega_c(3327)^0$, are
observed in the $\Xi_c^{+}K^{-}$ invariant-mass spectrum using proton-proton
collision data collected by the LHCb experiment, corresponding to an integrated
luminosity of $9\,{\rm fb}^{-1}$. Five previously observed excited $\Omega_c^0$
states are confirmed, namely $\Omega_c(3000)^0$, $\Omega_c(3050)^0$,
$\Omega_c(3065)^0$, $\Omega_c(3090)^0$, and $\Omega_c(3119)^0$. The masses and
widths of these seven states are measured with the highest precision to date.
