This paper deals with an inverse problem which consists in the location identification of multiple-line heat sources placed in an homogeneous solid in the stationary case. The location and strength of the line heat sources are unknown. The identification procedure is based on the boundary integral formulation using Green functions. The discretized problem is non-linear if the location of the line heat sources is unknown. In order to solve the problem we use an iterative procedure to minimize a quadratic norm. The proposed numerical approach is applied to an experimental 2D example using measurements provided by an infrared scanner. The number of line heat sources is supposed to be known but we give some examples involving a number of sources superior or inferior to the real number. (C) 2001 Elsevier Science Ltd. All rights reserved.