An unstable fishbone-like non-resonant external kink mode (FLEM) is numerically found to be driven by the precessional drift motion of trapped energetic particles (EPs) in both RFP and Tokamak plasmas. The FLEM originates from a stable external ideal kink mode, which is stabilized by a close-fitting ideal conducting wall. In the presence of a sufficiently large fraction of EPs in the plasma, and with the satisfaction of the resonance condition, the FLEM instability occurs. The frequency of the FLEM, therefore, varies with the plasma flow speed, and is usually much higher than that of the typical resistive wall mode (RWM). In general, the growth rate of FLEM does not depend on the wall resistivity. However, the wall position can significantly affect the mode’s property. The drift kinetic effects from thermal particles (mainly due to the transit resonance of passing particles) play a stabilizing role on FLEMs. In the presence of EPs, the FLEM and the RWM can co-exist or even couple to each other, depending on the plasma parameters. The FLEM instabilities in RFP and Tokamak have rather similar physics nature, although certain sub-dominant characters appear differently in the two configurations.