In the three days prior to the attack, we collected streams of human, signals and geospatial intelligence that reveal regime activities that we assess were associated with preparations for a chemical weapons attack. (…)

Multiple streams of intelligence indicate that the regime executed a rocket and artillery attack against the Damascus suburbs in the early hours of August 21. Satellite detections corroborate
that attacks from a regime-controlled area struck neighborhoods where the chemical attacks reportedly occurred – including Kafr Batna, Jawbar, ‘Ayn Tarma, Darayya, and Mu’addamiyah.
This includes the detection of rocket launches from regime-controlled territory early in the morning, approximately 90 minutes before the first report of a chemical attack appeared in social media.