''Dark beams'' are nonuniform optical beams that contain either a one-
dimensional (1D) dark stripe or a two-dimensional (2D) dark hole resul
ting from a phase singularity or an amplitude depression in their opti
cal field. Thus far, self-trapped dark beams (dark solitons) have been
observed using coherent light only. Here, self-trapped dark incoheren
t light beams (self-trapped dark incoherent wavepackets) were observed
. Both dark stripes and dark holes nested in a broad partially spatial
ly incoherent wavefront were self-trapped to form dark solitons in a h
ost photorefractive medium. These self-trapped 1D and 2D dark beams in
duced refractive-index changes akin to planar and circular dielectric
waveguides. The experiments introduce the possibility of controlling h
igh-power coherent laser beams with low-power incoherent light sources
such as light emitting diodes.