A violent separatist campaign by the Ansata of the western continent of Rutia IV, which drew in the Enterprise-D when its leader abducted Beverly Crusher and later Captain Picard.
In The Next Generation episode The High Ground, the Enterprise-D is delivering medical supplies to Rutia IV when a bomb goes off in a square. Doctor Crusher stops to treat the wounded and is seized by Ansata fighters, who vanish using an inverter, a dimensional-shift device that no sensor can follow but which is slowly killing those who use it.
Their leader, Kyril Finn, wants Crusher to treat his people and hopes to force the Federation to take a side. He argues his cause to her with some effect. Riker works with the Rutian security chief, Alexana Devos, whose methods have hardened after years of attacks.
The Ansata raid the Enterprise, nearly destroying it with a charge on the warp core, and carry off Picard. Wesley Crusher and Data find a way to trace the inverter, and a joint raid frees the hostages. Devos shoots Finn dead.