The IKS Bortas was a Klingon D5-class battle cruiser in service to the Klingon Empire's Klingon Defense Force in the mid-22nd century. She was under the command of Captain Duras.
The Bortas engaged the United Earth Starfleet starship Enterprise in the year 2152, when the latter rendered aid to a refugee ship. (This refugee ship was transporting fugitives from a planet the Klingons had recently annexed.) Enterprise successfully escaped the battle cruiser by blinding their sensors with a carefully placed shot into a gas giant's rings, thus concealing the retreat of the Terran ship. (ENT episode: "Judgment")