That request was based on information that Tamerlan was a follower of radical Islam and was preparing to «leave the United States for travel to the country's region to join unspecified underground groups.» (businessinsider.com)
The Soviet Union today is honeycombed with small underground groups — which help to explain why «civil rights», issues are so threatening to the government there. (religion-online.org)
Isabelle quickly becomes involved in underground groups to subvert the Nazis, working her way from someone who passes out anti-Nazi propaganda, to a woman who leads Allied forces to safety, crossing the Pyrenees mountains to do so. (books-n-cooks.com)