Recently several techniques that provide different degree of anonymity have been proposed for wired and wireless communication. Although, the recently proposed techniques are successful in achieving high degree of anonymity, there are some disadvantages associated with the proposed techniques. In this paper we analyze the flooding and packet drop attacks in mobile ad hoc networks that support anonymous communication. Then we propose a novel technique to deal with the flooding attacks. Our approach can efficiently identify and isolate the malicious node that floods the network. In addition, our technique provides a mechanism to identify the benign behavior of an expelled node and rejoins the expelled node back into the network. Furthermore, our approach does not require any additional packets to communicate the behavior of the flooding node and hence does not incur any additional overhead. Finally we validate the performance analysis of our technique through NS2 simulations.