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The NGC 2024 FIR 5/6 region was observed in the 6.9 mm continuum with anangular resolution of about 1.5 arcsec. The 6.9 mm continuum map shows fourcompact sources, FIR 5w, 5e, 6c, and 6n, as well as an extended structure ofthe ionization front associated with the optical nebulosity. FIR 6c has asource size of about 0.4 arcsec or 150 AU. The spectral energy distribution(SED) of FIR 6c is peculiar: rising steeply around 6.9 mm and flat around 1 mm.The possibility of a hypercompact H II region is explored. If the millimeterflux of FIR 6c comes from hot ionized gas heated by a single object at thecenter, the central object may be a B1 star of about 5800 solar luminositiesand about 13 solar masses. The 6.9 mm continuum of FIR 6n may be a mixture offree-free emission and dust continuum emission. Archival data show that bothFIR 6n and 6c exhibit water maser activity, suggesting the existence of shockedgas around them. The 6.9 mm continuum emission from FIR 5w has a size of about1.8 arcsec or 760 AU. The SEDs suggest that the 6.9 mm emission of FIR 5w and5e comes from dust, and the masses of the dense molecular gas are about 0.6 and0.5 solar masses, respectively.

Radio Imaging of the NGC 2024 FIR 5/6 Region: a Hypercompact H II Region Candidate in Orion