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A 100 mJ, 100 ns pulsed CO2 laser incident on the surface of soil is used as a localized acoustic source for the detection and imaging of underground objects. The acoustic pulse produced by the impulsive heating of the soil surface due to the absorbed 10.6 μm radiation is detected with an acoustic transducer suspended over the surface. Application of a Fourier domain filter enables the separation of the direct acoustic return from the faint echo from an object buried 3–25 mm below the surface. Scanning of the laser pulses across the position of a buried object allows the resolution of the shape and the depth of the buried object. The application of this technique to image buried landmines is demonstrated in trials at an outdoor test track.