A magnetic signature minesweeping device comprising a water driven turbine power generator and a superconducting material magnet, wherein the turbine power generator is arranged, in use, to supply a driving current for the superconducting material magnet when the minesweeping device is towed through the water. In a further embodiment, a control unit is arranged, in use, to control the magnetic output of the superconducting magnet and the power output of the turbine power generator. Furthermore, a method of minesweeping using the device and an array of the devices is disclosed.