An unmanned supply rocket bound for the International Space Station has exploded during its launch from the US state of Virginia.
Antares, a 14-storey rocket built by Orbital Sciences Corp, combusted seconds after leaving the seaside launch pad at Wallops Flight Facility.
The cause of the cargo ship malfunction has yet to be determined.
The initial planned launch of the spacecraft on Monday was delayed due to a yacht in the surrounding danger zone.
The flight was expected to be the third contracted mission with the National Aeronautics and Space Administration.
The rocket was due to carry nearly 5,000 pounds (2,200kgs) of supplies to six astronauts aboard the International Space Station.
“We will understand what happened, hopefully soon, and we’ll get things back on track,” said Frank Culbertson, executive vice-president of Orbital Sciences.
“We’ve all seen this happen in our business before, and we’ve all seen the teams recover from this, and we will do the same.”
No-one was injured, said Mr Culbertson, and an investigation team was already going through the data to try to establish the cause.
On Wednesday morning, he said, the examination of debris around the site would begin.
The investigation will not jump to conclusions but one line of inquiry will surely focus on the AJ-26 engines used to lift the rocket away from the pad, says BBC science correspondent Jonathan Amos.
“These are actually modified Russian-built power units that were originally developed for the ill-fated Soviet Moon rocket, the N-1.
“They have been refurbished to modern standards, but one blew up in ground testing earlier this year.”