Even Odds disaster

The Even Odds disaster was an event that took place in the Bajor system in 2377. Following an Ascendant incursion into the system via the Bajoran wormhole, an Isolytic subspace weapon was detonated by Taran'atar from aboard the Even Odds. The disaster had both immediate and long term effects, some that would not be discovered for years.

Prelude
In 2377, the Prophets named Iliana Ghemor as "the Fire" and sent her to a meeting of the Ascendants in the Gamma Quadrant. Ghemor was accepted as a religious leader by the Ascendants and she took possession of a subspace weapon. Ghemor planned to take revenge on Kira Nerys and the Bajoran people by detonating the weapon in orbit of Bajor. Prior to this, the Ascendant fleet attacked the Eav'oq city of Terev'oqu, although the attack was thwarted due to the intervention of Taran'atar and Vedek Kira Nerys, who the Prophets had sent back in time. Ghemor decided to leave the Ascendant fleet at Idran IV, although once her ship left the planet for the wormhole with the weapon, the Ascendant fleet soon followed her. 

The Ascendant invasion
The Ascendant fleet soon entered the Alpha Quadrant and refused to answer hails from Captain Kira Nerys on Deep Space 9. Kira ordered phasers and quantum torpedoes to be fired on the lead ship, to a negligible effect on the strong Ascendant shields. Kira was forced to allow the fleet to carry on towards Bajor.