A SpaceX rocket carrying supplies to the International Space Station has blown up shortly after lifting off from Cape Canaveral, Florida.
Nasa says the accident came a few minutes into the flight. Debris could be seen falling into the Atlantic.
Nasa commentator George Diller says "the vehicle has broken up". He says it is not clear how the disaster happened.
This is the second failed station shipment. In April, a Russian cargo ship spun out of control and came down. And last October, another company's supply ship was destroyed in a launch accident.
SpaceX says the initial part of the lift-off went well, until the vehicle went supersonic.