  We demonstrate the existence of spherically-symmetric truly naked black holes
(TNBH) for which the Kretschmann scalar is finite on the horizon but some
curvature components including those responsible for tidal forces as well as
the energy density $\bar{\rho}$ measured by a free-falling observer are
infinite. We choose a rather generic power-like asymptotics for the metric
functions and analyze possible types of a horizon depending on the behavior of
curvature components in the free-falling frame. It is also shown in a general
case of distorted black holes that $\bar{\rho}$ and tidal forces are either
both finite or both infinite. The general approach developed in the article
includes previously found examples and, in particular, TNBHs with an infinite
area of a horizon. The fact that the detection of singularity depends on a
frame may be relevant for a more accurate definition of the cosmic censorship
conjecture. TNBHs may be considered as a new example of so-called non-scalar
singularities for which the scalar curvature invariants are finite but some
components of the Riemann tensor may diverge in certain frames.
