Due to the increasing demand for security,the development of intelligent surveillance systems has attracted considerable attention in recent years.This study aims to develop a system that is able to identify whether or not the people need help in a public place.Different from previous work,our work considers not only the behaviors of the target person but also the interaction between him and nearby people.In the paper,we propose an event alarm system which can detect the human behaviors and recognize the happening event through integrating the results generated from the single and group behavior analysis.Several new effective features are proposed in the study.Besides,a mechanism capable of extracting one-to-one and multiple-to-one relations is also developed.Experimental results show that the proposed approach can correctly detect human behaviors and provide the alarm messages when emergency events occur. Due to the increasing demand for security, the development of intelligent surveillance systems has attracted seems attention in recent years. This study aims to develop a system that is able to identify whether or not the people need help in a public place. Different from previous work , our work considers not only the behaviors of the target person but also the interaction between him and nearby people.In the paper, we propose an event alarm system which can detect the human behaviors and recognize the happening event through integrating the results generated from the single and group behavior analysis. New effective effective are are in the study. Besides, a mechanism capable of extracting one-to-one and multiple-to-one relations is also developed. Experimental results show that the proposed approach can correctly detect human behaviors and provide the alarm messages when emergency events occur.