The infrastructure of large cities is getting more and more vulnerable to natural and man-made disasters. Complex ICT infrastructures, critical dependencies and unforeseen cascading effects can aggravate single hazard events to a threatening crisis of whole infrastructures. With the dense population and the critical dependency on infrastructures, such crises become a serious threat to the safety and security of citizens and industries. When the "unforeseen" happens, public security comes to its limits. Whether cyber, natural or industrial disasters - effective risk management must be a continuous process that recognizes new threats and opportunities, in particular in relation to new technological evolutions. Internet of Things (IoT) will have an enormous impact on our future infrastructures. In the context of safety and security this is at the same time a challenge (How can we design IoT infrastructures secure and resilient?) and an opportunity (How can we use IoT for better safety and security?). In particular in urban environments, the increasing deployments of IoT technologies and the rise of sensored and automated cities are opening up new avenues of threads and opportunities towards public safety and security. Although, there have been a number of deployment of diverse IoT systems, our understanding of these systems and their implications in the context of safety and security has just scratched the surface.