We report the detection of extended infrared emission 5.2 kpc above and below the plane of the edgeon spiral galaxy NGC 5907 in the J and K bands. This provides confirmation at two other wavelengths of the R band result of Sackett et al. (1994). The halo J--K colour was found to be 1.3±0.3. The K surface brightness and P-K colour were found to be 23.0 mag. arcsec-2 and 3.5 respectively, and if we interpret the observed emission as coming from the massive component that causes the flat rotation curve, the M/LK ratio is 115 in solar units. All three numerical values are somewhat dependent on the assumed functional form of the halo. These results are broadly consistent with a population of stars at the very lowest masses, possibly extending into the brown dwarf regime.
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