U.S. surveillance satellites detected Iran readying drones and missiles at launch sites in Iran before Saudi oil facilities were attacked on Saturday, according to two Defense Department officials.

The imagery has not been publicly released. The officials tell NPR that U.S. intelligence views the activity as "circumstantial evidence" that Iran launched the strike from its own soil.

Sounds pretty plausible to me.

I could not get link to open.

Will repost.