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We report the first detection of metric radio emission from a surge, observedwith the Nan\c{c}ay Radioheliograph (NRH), STEREO and other instruments. Theemission was observed during the late phase of the M9 complex eventSOL2010-02-012T11:25:00, described in a previous publication and was associatedwith a secondary energy release, also observed in STEREO 304 {\AA} images:there was no detectable soft X-ray emission. Triangulation of the STEREO imagesallowed the identification of the surge with NRH sources near the centralmeridian. The radio emission of the surge occurred in two phases and consistedof two sources, one located near the base of the surge, apparently at or nearthe site of energy release, and another in the upper part of the surge; thesewere best visible in the frequency range of 445.0 to about 300MHz, whereas aspectral component of different nature was observed at lower frequencies.Sub-second time variations were detected in both sources during both phases,with 0.2-0.3s a delay of the upper source with respect to the lower, suggestingsuperluminal velocities. This effect can be explained if the emission of theupper source was due to scattering of radiation from the source at the base ofthe surge. In addition, the radio emission showed signs of pulsations andspikes. We discuss possible emission mechanisms for the slow time variabilitycomponent of the lower radio source. Gyrosynchrotron emission reproduced fairlywell the characteristics of the observed total intensity spectrum at the startof the second phase of the event, but failed to reproduce the high degree ofthe observed circular polarization as well the spectra at other instances. Onthe other hand, type IV-like plasma emission from the fundamental could explainthe high polarization and the fine structure in the dynamic spectrum; moreover,it gives projected radio source positions on the plane of the sky, as seen fromSTEREO-A, near the base of the surge. Taking everything into consideration, wesuggest type IV-like plasma emission with a low intensity gyrosynchrotroncomponent as the most plausible mechanism.

First detection of metric emission from a solar surge