The cause

A single misclick.

No, really: A Titan pilot beneath the Cluster banner was attempting a “bridge”—using a ship to act as an artificial warp corridor for other ships—to Asakai VI when he accidentally warped himself straight into a very surprised Pandemic Legion fleet. The pilot, named Dabigredboat, immediately came under heavy attack as the Legion pounced on the extremely valuable ship.

via EVE Online’s Battle of Asakai: who was involved, the stakes, and the aftermath | News | PC Gamer.

I sometimes find the drama in these MMORPG fascinating and Eve Online usually has the best stories.  The cynical side of me suspects this might have been staged as a marketing promotion.   I hear nothing but good things about Eve Online however.