Unmanned US rocket Antares explodes during launch

An unmanned Antares rocket exploded seconds after liftoff from a commercial launch pad on Virginia's eastern seaboard on Tuesday, marking the first accident since NASA turned to private operators to deliver cargo to the International Space Station.

It burst into flames moments later, then plunged to the ground in a huge ball of fire and smoke, but authorities said no one was hurt. The cause of the mishap was under investigation, said Frank Culbertson, Orbital Sciences executive vice president.

The 14-story rocket, built and launched by Orbital Sciences Corp, blasted off from its launch pad at the Wallops Flight Facility at 6:22 p.m. EDT/2222 GMT, carrying a Cygnus cargo ship bound for the space station.

Footage of Tuesday's launch showed the Antares rising slowly into the night sky as flames suddenly engulfed the rocket, from the bottom to the top about 11 seconds after liftoff, before the vehicle sank back downward in a conflagration.