I. Introduction
We live in the generation of social networks. Like online social networks facebook and twitter have become quite popular in couple of years. Many people use social networks to perform different activities online like staying in contact with relatives, friends, chatting and also acquiring information and news. This creates interactions between different users forming an activity log. These information are stored by the social network service providers. The access of such information to a spam user may expoit the privacy and security of the social network. It may also spread some illegal content and wrong information. These users or accounts gain access to information of other users or spread unwanted messages. Comman spam behaviors like Sybil attacks occur in online social networks. Therefore identifying the spam user is a necessity.