Update 12:45 p.m.
Video footage of the SpaceX rocket exploding on the launch pad at Cape Canaveral has emerged.
The video above, posted by nonprofit, veteran-run organization U.S. Launch Report, shows the Falcon 9 burst into flames during testing at the Kennedy Space Center on Thursday morning.
Nobody was injured in the explosion, which was caused by an "anomaly at the pad," according to SpaceX, with the rocket and its payload – which included Facebook's first ever satellite – destroyed in the blast.
An explosion on the launch pad is being reported at Cape Canaveral in Florida, as preparations were taking place for an unmanned rocket launch.
A webcam from the Kennedy Space Center shows a large plume of black smoke is coming from the pad, where the SpaceX company was readying for a launch of its Falcon 9 rocket.
SpaceX has made a statement, saying it lost both the rocket and payload in the explosion, which was caused by an "anomaly" at the pad.
TechCrunch reports was due to launch on Saturday, to deliver Facebook's first satellite into orbit.
A picture from Reddit user MTrevor123 (see above) shows a fireball emanating from the launch site, with nearby properties said to have shook when it happened.
Local responders referred to the explosion as resulting from a "catastrophic abort."
David Shukman, the science editor at BBC News, says the explosion is bad news for SpaceX's "big dreams for cheap, frequent and distant space travel," saying the test-firing "was meant to be routine, part of an accelerating series of launches."
The company, owned by Tesla and PayPal founder Elon Musk, is trying to make history by making reusable rockets, and is also working on ambitious plans to create a colony on Mars.