He proceeded to take a relatively undefended fortress. In 1740, Prussian troops crossed over the undefended border of Silesia and occupied Schweidnitz. Cities became walled, and increased in size as undefended villages in southern Mesopotamia disappeared. This is a claim which historian David Henige describes as "undefended" and "indefensible". The undefended Jesuit missions were attacked by the Brazilian Bandeirantes. The Cimbri were also able to ransack Caepio's camp, which had been left practically undefended. Mosul threw off its dependence, and the Greeks raided across the undefended border. The opponent has the unpalatable choice of recapturing or saving the undefended piece. In Norway, a company of paratroopers dropped at Oslo's undefended airstrip. Phillips then advanced again against the largely undefended countryside. A power vacuum occurred on the now undefended Rhine border. They found that the beach was undefended but unsuitable for an amphibious landing. Their objective was the undefended Norwegian Lofoten Islands. Traction trebuchets were to be used for hitting people in undefended areas. Canada shares with the U.S. the world's longest undefended border at ; are with Alaska.