  We calculate target fragmentation in $p p \to n X$ and $\gamma p \to n X $
reactions in the meson cloud picture of the nucleon. The $p p \to n X$ reaction
is used to fix the $pn\pi^+$ form factor for three different models. We take
into account the possible destruction of the residual neutron by the
projectile. Using the form factor from the hadronic reaction we calculate
photoproduction and small $x_{Bj}$ electroproduction of forward neutrons at
HERA. Here the $q \bar q$ dipoles in the photon can rescatter on the residual
neutron. In photoproduction we observe slightly less absorption than in the
hadronic reaction. For deep inelastic events ($Q^2>10$ GeV$^2$) screening is
weaker but still present at large $Q^2$. The signature for this absorptive
rescattering is a shift of the $d\sigma/dE_n$ distribution to higher neutron
energies for photofragmentation.
