  We present low-temperature heat and charge transport as well as caloric
properties of a ThAsSe single crystal. An extra -AT1/2 term in the electrical
resistivity, independent of magnetic fields as high as 14 T, provides evidence
for an unusual scattering of conduction electrons. Additionally, both the
thermal conductivity and specific heat show a glass-type temperature dependence
which signifies the presence of tunneling states. These observations apparently
point to an experimantal realization of a two-channel Kondo effect derived from
structural two-level systems.
