Imaging surveys of dust emission at (sub)millimetre wavelengths provide a powerful tool for studying molecular clouds and the early stages of star formation. Through submm dust continuum mapping, we attempt to search for genuine infrared-dark clouds (IRDCs) and precursors to massive stars and stellar clusters in the Galactic plane, and to determine their basic physical properties. We have mapped four selected fields of about 0.5degx0.5deg that contain Spitzer 8-um dark regions with LABOCA at 870um. Selected positions in the fields were observed in C^17^O(2-1) to obtain kinematic information. The obtained LABOCA maps are used in conjunction with the Spitzer IR images.