  We report observations of GRB 050525A, for which a Gemini North spectrum
shows its redshift to be z = 0.606. This is the third closest long GRB
discovered by Swift. We observed its afterglow using the VLT, Gemini and TNG
telescopes to search for an associated SN. We find that the early-time light
curve is described by a broken power law with a break at t ~ 0.3 d after the
burst. About 5 d after the burst, a flattening is apparent, followed by a
further dimming. Both the magnitude and the shape of the light curve suggest
that a supernova was emerging during the late decay of the afterglow. This
supernova, dubbed SN 2005nc, had a rise time faster than SN 1998bw and a
long-lasting maximum. A spectrum obtained about 20 d (rest-frame) after the GRB
resembles the spectrum of SN 1998bw obtained close to maximum light.
