An unknown time before the Leviathan arrived at Farpoint, it destroyed the Ja'torb homeworld. Mustering the last of their Star Fleet, Ja'torb Supreme Admiral Kar'ra chased the ship through hyperspace and arrived at Farpoint some time after the Leviathan.
Mistakenly believing the ship was returning home, the Ja'torb attacked Rogue Squadron, declaring Ka're, their highest form of war.
Eventually the two forces reached an uneasy truce, and the fleet continued to follow the Leviathan after it was diverted away from Farpoint. The fleet hasn't been seen since and its fate after the Leviathan's death is uncertain.