In Wireless Sensor Networks, nodes regularly suffer from interference which is generated by devices working in the same frequency band. Thus, we propose a mechanism which: 1) identifies the percentage of interference in a wireless link; and 2) locates the source of interference. This mechanism is called Interference Characterization and Identification (ICI), and it comprises two phases: interference characterization and identification. In the first phase, we propose a novel metric called LP, which is based on measurements of latency and packet loss, in order to characterize the quality of the wireless link. In the second phase, we identify the percentage of interference of the wireless link by computing two statistical distances: Kolmogorov-Smirnov and Cramer-von Mises. Besides, in the second phase, we also determine whether the source of interference is close to the transmitter or the receiver. The results show that we can efficiently determine the percentage of interference in a wireless link and the location of the source of interference.