Jarok's scout ship was a Romulan scout ship.

When Alidar Jarok defected to the Federation in 2366, he appropriated this scout. The scout ship was pursued by a D'deridex-class warbird into Federation space, where it was intercepted by the USS Enterprise-D. Before Jarok was beamed over to the Enterprise, he set the ship's auto-destruct sequencer so that it would not be captured and studied by the Federation. (TNG: "The Defector")