  We study experimentally the dynamics of a dense intruder sinking under
gravity inside a vibrated 2D granular packing. The surrounding flow patterns
are characterized and the falling trajectories are interpreted in terms of an
effectivive friction coefficient related to the intruder mean descent velocity
(flow rules). At higher confining pressures i.e. close to jamming, a transition
to intermittent dynamics is evidenced and displays anomalous "on-off" blockade
statistics. A systematic analysis of the flow rules, obtained for different
intruder sizes, either in the flowing regime or averaged over the flowing and
blockade regimes, strongly suggest the existence of non-local properties for
the vibrated packing rheology.}
