[en] The anomalous eμ events produced in e⁺e^- annihilation, e⁺ + e^- → e^+- + μ^-+ + missing energy, (1) was explained as the decay products of a pair of U particles produced in the reaction e⁺ + e^- → U⁺ + U^-. (2) New data is presented on the U particles in the energy region just above their production threshold and results of a study of the nature of the particles carrying off the missing energy in Eq. (1). While presenting these new results the present status of knowledge of the anomalous eμ events and their U particle explanation is briefly reviewed. 19 references