The media did credit the source of information to an anonymous U.S. government official confirming the failure of the mission.
Northrop Grumman provided the satellite, for which government agency it wouldn't say.
A senior scientist at the Union of Concerned Scientists, Laura Grego, showed concern that the satellite might have stopped functioning near the orbit or failed to separate from the rocket during the second half of the mission.
The loss, if it was determined to be a failure of SpaceX hardware, could be a "real threat" to the company's future defense business, said Loren Thompson, defense analyst at the Lexington Institute.
SpaceX and Northrop Grumman have refused to address rumors that all may not be well with the classified "Zuma" satellite launched on Monday. If additional reviews uncover any problems, she said, "we will report it immediately".
"For clarity: after reviewing of all data to date, Falcon 9 did everything correctly on Sunday night".More news: Putin calls Kim Jong Un competent and mature politician
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SpaceX is the commercial launch service formed by Elon Musk, who is also CEO of Tesla.
Image copyright Getty Images Image caption A Space X rocket during launch. Info blackout renders any conclusion - launcher issue?
But Marco Caceres, senior space analyst at Teal Group, said SpaceX's cheaper launch costs and faster turnarounds for missions will still probably work in its favor with the Air Force, even if the Zuma mission were determined to be a launch failure. The company chose SpaceX as the launch provider, noting late a year ago that it took "great care to ensure the most affordable and lowest risk scenario for Zuma".
Elon Musk has announced that the first flight of his company's "Falcon Heavy" rocket will carry a Tesla Roadster - touted as the quickest vehicle in the world with record-setting acceleration, range and performance - into Martian orbit.
Just before 1 p.m., though, the company postponed the test fire.
This article was originally published by Futurism.