 The historian Christopher Othen claims the number to be closer to 8,000.A Portuguese Military Observation Mission with members drawn from all three branches of the Portuguese military was present in Spain from 1937 onwards, with the dual objectives of protecting the interests of Portuguese foreign volunteers and collating information on the lessons learned during the civil war.Although the mission officially had a noncombatant role, its air force contingent took part in combat missions, the aviator José Adriano Pequito Rebelo being a notable member.