This paper describes the development and deployment of a wireless sensor network for monitoring human motion and position in an indoor environment. Mobile sensor nodes comprising mote-type devices, along with inertial sensors are worn by persons moving inside buildings. Motion data is preprocessed onboard mobile nodes and transferred to a static network of seed nodes using a delay tolerant protocol with minimal radio packet overhead. A Monte Carlo based localisation algorithm is implemented, which uses a person's pedometry data, indoor map information and seed node positions to provide accurate, real-time indoor location information. The performance of the network protocols and localisation algorithm are evaluated using simulated and real experimental data.