U.S. Launch Report / Reuters

NEWS BRIEF Elon Musk, the SpaceX founder, says last week’s explosion of the Falcon 9 rocket in Cape Canaveral, Florida, days before a scheduled launch, is “turning out to be the most difficult and complex failure we have ever had in 14 years.”

SpaceX had called the September 1 explosion “an anomaly on the pad.” The crewless rocket was due to launch a satellite last weekend, and exploded during what Musk called a “propellant fill operation.” Early Friday, Musk offered more details about the ongoing investigation into what caused the rocket to explode.

When asked on Twitter about videos on YouTube that appeared to suggest something had hit the rocket, Musk replied: “We have not ruled that out.”

The destroyed Falcon 9 rocket was scheduled to take a satellite into orbit that Facebook planned to use to bring internet access to parts of the world where it is limited.

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