This article presents a social approach for disaster management based on a social portal called Disasters2.0, which provides facilities for integrating and sharing user-generated information about disasters. The architecture of Disasters2.0 is designed following Representational State Transfer (REST) principles and integrates external mashups such as Google Maps. This architecture has been consumed with different clients, including a mobile client, a multiagent system for assisting the decentralised management of disasters and an expert system for automatically assigning resources to disasters. As a result, the platform allows seamless collaboration of humans and intelligent agents, and provides a novel web 2.0 approach for multiagent and disaster management research.