United States

Aaron Alexis, a Navy veteran, shot and killed 12 people and wounded 14 more at the Navy Yard in Washington, D.C.; he was killed during the melee and his motive is unknown. The UN investigative report on the Aug. 21 chemical attack in Damascus concluded that sarin gas was used in surface-to-surface missiles in the area; the US and the UK insisted that the Assad regime had conducted the attack, and Russia differed, asking why no rebels were among the casualties. Following the report, UN Ambassador Samantha Power dismissed the claim that insurgents launched the attack as one that “defies logic.” President Obama signed an order to help protect Syrians against chemical weapon attacks by providing protective gear and training.

Iraq

Islamic state

Syria

Aqap

Al shabaab

Boko Haram

Isis