While the number of domestic terror incidents increases, law enforcement agencies are doing less to catch domestic extremists, a year-long investigation by the Kansas City Star has found.

The investigation revealed that after Sept. 11, 2001, law enforcement agencies turned their attention toward stopping foreign terrorism at a degree that deemphasized efforts to stop domestic terrorists. “Fusion centers” set up to stop terrorism after 9/11 have largely disrupted police efforts.

Domestic extremists have killed more than 50 people since 9/11.

For the full series, click here. For an interactive feature of mini-stories about specific attacks, click here.