To confuse matters further, the Falcon 9's first stage was able to successfully land back on Earth, indicating that the rocket was still fully operational.
To add to the mystery status of Zuma mission, the satellite is still categorized as a payload by the US space-based surveillance system.
Its Falcon 9 rocket "performed nominally", it said.
SpaceX denied providing any comment related to the mission as it contained confidential information. If additional reviews uncover any problems, she said, "we will report it immediately".
Also, the future flights of SpaceX will remain scheduled as they were. "Though we have preserved the range opportunity for tomorrow, we will take the time we need to complete the data review and will then confirm a new launch date".
Falcon Heavy launches start at $90 million, compared to the starting price of $62 million for the smaller Falcon 9, according to SpaceX's website.
Gwynne Shotwell, the chief operating officer of SpaceX, issued a strongly worded statement on Tuesday that placed the blame elsewhere. The flight seemed to go off without a hitch, although we weren't given full access to video throughout the entirety of the flight or detailed telemetry data considering that this was a classified mission for the U.S. Military.
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On launch day, safely tucked away in a protective payload fairing will be Musk's 2008 Tesla Roadster, an all-electric sports vehicle that boosted his energy company during its formative years.
In the meantime, Falcon Heavy, like its smaller cousin the Falcon 9, will advance SpaceX's goal of cutting launch costs by reusing rockets.
Under mounting pressure from SpaceX, ULA's CEO Tory Bruno vowed to "literally transform" the company to compete - and he also continued to champion ULA's track record of successful launches of more than 100 in a row.
Senator Bill Nelson (D-FL), who previous flew into space in the 1980s aboard Columbia as a payload specialist, sided with SpaceX, stating, "The first statement by SpaceX was that the failure to achieve orbit was not theirs".
On the heels of the Falcon Heavy and Falcon 9/GovSat 1 missions later this month, SpaceX plans at least two launches in February for two Spanish customers.
In May 2017, SpaceX managed to recover the first stage of a rocket that it used to launch a classified USA reconnaissance satellite.
It was one of the most important things Elon Musk has ever launched into space: a government satellite so shrouded in secrecy that virtually everything about it is classified.