Iran is suspected of moving its stockpile of highly enriched uranium into its deepest underground site and possibly building a weapon there — bad news for anyone hoping the nuclear standoff has cooled off.

• Satellite images showed trucks pulling up to Iran's enrichment sites, suggesting the material was hauled away before strikes.
• The likely destination is Pickaxe Mountain, a facility buried deep enough to survive bombing.
• Iran holds roughly 460 kg of highly enriched uranium — enough to matter, and now hard to track.
• US intelligence is believed to know where it went, which raises the odds of further military action.

Outlook: Pressure builds for another round of strikes or inspections, with Iran's deepest sites now the focus.