  This rapporteur review covers selected results presented in the Parallel
Session HEA2 (High Energy Astrophysics 2) of the 10th Marcel Grossmann Meeting
on General Relativity, held in Rio de Janeiro, Brazil, July 2003. The subtopics
are: ultra high energy cosmic ray anisotropies, the possible connection of
these energetic particles with powerful gamma ray bursts, and new exciting
scenarios with a strong neutrino-nucleon interaction in the atmosphere.
