The White House says President Barack Obama will make a statement shortly on the first round of airstrikes by the US-led coalition against Islamic State militants in Syria.
The US and a group of five Arab countries conducted 14 bombings that damaged or destroyed targets in eastern Syria, including in the Islamic State group's main stronghold of Raqqa.
Bahrain, Qatar, Saudi Arabia, Jordan and the United Arab Emirates either participated in or supported the attacks, which hit training compounds, militant headquarters and a finance center.
The London-based Syrian Observatory for Human Rights reported the airstrikes killed or wounding tens of militants.