Ship Hit Near Hormuz — Who's Responsible?

Who fired it, and why now, in the middle of active diplomacy rather than before or after? A cargo ship was struck by a projectile near the Strait of Hormuz, forcing its crew to abandon vessel, with one seafarer still missing and roughly a fifth of the world's oil trade passing through those waters every day. Is this a rogue attack meant to derail the talks, or a calculated signal from someone at the table?