AMMAN, Jordan -- A prominent Palestinian writer who was jailed in Syria for nearly three weeks described the facilities as "human slaughterhouses," saying security agents beat detainees with batons, crammed them into stinking cells and tied them to beds at night.Salameh Kaileh, 56, was arrested April 24 on suspicion of printing leaflets calling for the ouster of Syrian President Bashar Assad, who is fighting a 15-month-old uprising against his rule.