Syrian government forces conducted coordinated chemical attacks in opposition-controlled parts of Aleppo during the final month of the battle for the city, Human Rights Watch said Feb. 13. Through phone and in-person interviews with witnesses and analysis of video footage, photographs, and posts on social media, Human Rights Watch documented government helicopters dropping chlorine in residential areas on at least eight occasions between Nov. 17 and Dec. 13, 2016. The attacks, some of which included multiple munitions, killed at least nine civilians, including four children, and injured around 200. The attacks took place in areas where government forces planned to advance, starting in the east and moving westwards as the frontlines moved, Human Rights Watch said.

"The pattern of the chlorine attacks shows that they were coordinated with the overall military strategy for retaking Aleppo, not the work of a few rogue elements," said Ole Solvang, deputy emergencies director at Human Rights Watch. "The United Nations Security Council shouldn’t let Syrian authorities or anyone else who has used chemical weapons get away without consequences."

The UN Security Council has yet to take action since a UN-appointed investigation, known as the Joint Investigative Mechanism, identified military units responsible for earlier attacks using chlorine in Syria. The Security Council should impose sanctions on senior leaders in the chain of command, Human Rights Watch said. (HRW, Feb. 13)