The Nizak are a sentient civilization. Cortin Zweller once described the Nizak as being reptilian and meat-eating, with a civilization geared towards conquest. In the 24th century, the Nizak were conducting warp drive tests. Starfleet had identified the Nizak as a possible threat to more than a dozen Federation worlds near their planet, so Section 31 sabotaged the warp program by destroying the Nizak prototype warp spacecraft. (TNG - Section 31 novel: Rogue)