MARFE instabilities and UFOs leave clear signatures in JET fast visible camera videos. Given the potential harmful consequences of these events, particularly as triggers of disruptions, it would be important to have means of detecting them automatically. In this paper, the results of various algorithms to identify automatically MARFEs and UFOs in JET visible videos are reported. The objective is to retrieve videos, which have captured these events, exploring the whole JET database of images, as a preliminary step to the development of real time identifiers in the future. For the detection of MARFEs, a complete identifier has been finalized, using morphological operators and Hu moments. The final algorithm manages to identify videos with MARFEs with a success rate exceeding 80%. Due to lack of a complete statistics of examples, the UFO identifier is less developed but a preliminary code can detect UFOs quite reliably.