In an alternate timeline, the Tandaran Empire was an interstellar state controlled by the Tandarans. Its homeworld was Tandar Prime.
The military branch of the Tandaran Empire was the Temporal Warfare Division (TWD). Its ships were equipped with chroniton-based torpedoes and were capable of jumping through time at will.
There also existed a Starfleet in the same reality.
In the year 2373, Professor Vard from this reality arrived at Aldebaran III in the primary universe. He attempted to evade the TWD. While being interviewed in the DTI Branch Office in Sadvis, a Tandaran ship materialized in the system and disabled the starship Cyrus with a single shot. Using his track-jumper, Vard fled to another reality to escape the TWD. The ship presumably followed him. (DTI novel: Watching the Clock)