"Preliminary indication is that we had an oxygen/fuel leak in the cavity above the ship engine firewall that was large enough to build pressure in excess of the vent capacity."

After the successful booster recovery, SpaceX officials reported losing contact with the spaceship toward the end of the ascend.

The last time a Starship upper stage failed was in March last year, as it was reentering Earth's atmosphere over the Indian Ocean, but rarely has a SpaceX mishap caused widespread disruptions to air traffic.