Officials concerned Iran may be emboldened after Trump appears to dismiss incident as a possible accident; White House invites House, Senate leaders for briefing

Rhetoric escalates as Revolutionary Guard chief threatens: 'Any enemy that violates the borders will be annihilated'

Former VP and presidential hopeful says it 'sadly ironic' that State Department 'now calling on Iran to abide by the very deal the administration abandoned'

Shin Bet accuses Jordanian national of working on behalf of Tehran to establish spy ring in Israel and West Bank, funnel money to Palestinian terrorists

US Central Command confirms aircraft shot down by surface-to-air missile; Revolutionary Guard says drone switched off tracking equipment; Iran warns US against violating airspace

Gen. Hossein Salami says country is ready for war though no 'intention' for it; US official: Drone was shot down by surface-to-air missile in international airspace

Tehran reportedly used surface-to-air missile; Iran's Revolutionary Guard says it hit Global Hawk as it entered Iranian airspace

State media says Global Hawk hit when it entered Iranian airspace in southern Iran's Hormozgan province; US military declines to comment

At House hearing, Democrats grill Brian Hook over US president's policy toward Tehran, warn it could lead to a war rather than negotiations

US-Iran tensions spike as five US-linked sites attacked within five days, apparently from Shiite areas