In this article social and information network theory is used to study information flows through the incident command post in a large-scale emergency operation. The case presented is the 2011 terrorist attacks in Norway. The data were collected from evaluation reports, media and interviews with the incident, fire, medical and ambulance commanders. The article presents the incident command system in Norway and how this was used as a base for improvisation during the operation on initiative from rescue workers on scene. The main internal information flows in each separate rescue service were connected and coordinated at the incident command point through strong ties between the commanders. Important and novel information also reached the commanders through weak and informal ties to more peripheral actors.