Originally posted by the Voice of America. Voice of America content is produced by the Voice of America, a United States federal government-sponsored entity, and is in the public domain. A Day After Deadly Gas Attack in Kahn Sheikhoun, Syria The gas attack at Kahn Sheikhoun, described by the opposition Syrian National Coalition as a "horrifying massacre," is widely believed to be the worst such violation of international law in war-ravaged Syria since 2013, when a U.N. probe found credible evidence that sarin gas killed hundreds of civilians near Damascus.