We generalize the Megyesi construction for Rédei minimal
blocking sets by placing cosets of a multiplicative subgroup of
on
lines of the
affine plane. These points together with the determined directions give a minimal blocking
set
with
. We also investigate
some constructions in
.
We show that if there is a minimal blocking set of size
in
, then minimal
blocking sets of size
and
exist
in
,
which are not necessarily of Rédei type.