The Numiri were a spacefaring humanoid race found in the Delta Quadrant. In the 2370s, they were engaged in a war with the Banea, with whom they once shared a planet. The Numiri had a remarkably covert society, and according to Neelix, they never needed an excuse to attack anyone.
They made use of such advanced technology as regenerative shielding, and their directed energy weapons were also equivalent of that of a Federation Intrepid-class vessel. Their patrol vessels were small but advanced enough to stand up to an assault by a Starfleet vessel; however, their sensor technology could not automatically detect the presence of a Starfleet shuttlecraft.
As part of their conflict with the Banea, they considered the area of the Banean planet a warzone, conducting patrols near the Banean planet and tending to intimidate travelers to it.
In 2371, Numiri agents attempted to frame USS Voyager crew member Tom Paris for their assassination of Banean weapons designer Tolen Ren. As by Banean law, Paris was forced to experience the memories of the murder every fourteen hours. The Banean doctor who performed the procedure was the real murderer and a Numiri agent, who hid the data on Ren's weapons research in the memory engrams. If Paris suspected anything, he would have believed that the symbols were part of the procedure. Twice the Numiri assaulted Voyager to capture Paris, only to fail each time. Tuvok was able to divulge the truth behind the murders and the Numiri attacks. Those complicit in the murder were arrested and the memories removed from Paris, leaving the Numiri with nothing. (VOY: "Ex Post Facto")