Margot Williams

Opening statements are set to begin Thursday in Boston at the trial of Tarek Mehanna, a 29-year-old American charged in U.S. District Court with conspiracy and providing material support to al-Qaida, as well as planning to attend training camps abroad and making false statements to authorities. He faces a possible life sentence if convicted.

Five men convicted in a recent wave of high profile domestic terrorism cases are now in special communications management units (CMUs) in the American Midwest, where their conversations are monitored 24 hours a day by counterterrorism analysts at the U.S Bureau of Prisons in West Virginia.

A new analysis by NPR's Investigations unit shows several new arrivals into the secretive CMU units, based in Terre Haute, Ind. and Marion, Ill.: