  Magnetoresistance (MR) and magnetization (d.c and a.c) measurements have been
carried out on the manganites, (La0.7-2xEux)(Ca0.3Srx)MnO3 (0.05<x<0.15), in
the temperature range of 5K-320K. At 5K, an unusually large MR of almost 98% is
observed in the x=0.15 sample, nearly up to fields of 4-5 Tesla. This large
high-field MR occurs in the metallic region, far below the insulator-metal
transition temperature, and does not vary linearly with applied field. The
unusual magnetoresistance is explained the light of various possibilities of
phase segregation and cluster spin-glass behavior. Keywords: Manganites, High
field MR, Phase segregation.
