The launch took place at the Cape Canaveral Air Force Station in a mission to deploy classified material for the United States National Reconnaissance Office.
It was the first launch since a new satellite for radio subscription service SiriusXM was sent into space on Dec. 13. It was also the company's second launch for the USNRO.
SpaceX sent up another classified payload for the agency in 2017.
The process was divided into three steps: an engine cut-off, a stage separation and a second engine start.
Following stage separation, SpaceX landed Falcon 9's first stage at Cape Canaveral's Landing Zone 1.
It was the final launch this year for SpaceX.
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