  We treat the production of neutrons, photons, and neutrinos through
photomeson interactions of relativistic protons with ambient photons in the
compact inner jets of blazars. We show that the presence of the external UV
radiation field makes possible strong energy losses already for protons with
energies > 1 PeV, while without this component effective energy losses of
protons begin only at E > 10^{18} eV. We develop a model describing the
production and escape of neutrons from a comoving spherical blob, which
continue to interact with the ambient external radiation field on the
parsec-scale broad line region (BLR). Neutrons may carry ~10% of the overall
energy of the protons accelerated beyond E ~ 1 PeV outside the BLR. Ultra-high
energy (UHE) gamma rays produced in photomeson interactions of neutrons outside
the blob can also escape the BLR. The escaping neutrons, gamma rays and
neutrinos form a collimated neutral beam with a characteristic opening angle ~
1/Gamma, where Gamma is the bulk Lorentz factor of the inner jet. The energy
and the momentum of such beam is then mostly deposited in the extended jet due
to neutron decay at distances ~ (E_n/10^{17} eV}) kpc, and through
pair-production attenuation of gamma rays with energies E_g ~ 10^{15}-10^{18}
eV which can propagate to distances beyond (10-100) kpc. In this scenario,
neutral beams of UHE gamma rays and neutrons can be the reason for straight
extended jets such as in Pictor A. Fluxes of neutrinos detectable with km-scale
neutrino telescopes are predicted from flat spectrum radio quasars such as 3C
279.
