On the 1st of September 2016 a SpaceX Falcon 9 rocket exploded during the final minutes of a simulated countdown at Cape Canaveral. The launch vehicle was carrying the AMOS-6 communications satellite which was regrettably destroyed during the explosion. This unfortunate event will also lead to a delay on launch support missions that SANSA Space Operations was scheduled to support due to the fact that there is an investigation underway.
According to the updates from SpaceX, during the time of the loss, the launch vehicle was vertical and in the process of being fuelled for the test. The data indicates that the anomaly originated around the upper stage liquid oxygen tank. All personnel were clear from the launch pad and there were no injuries.
A detailed report of the explosion and ongoing investigation is available here: