This paper presents a control strategy for multiple heterogeneous robots oriented to the assistance in situations of search and rescue from two complementary perspectives, the real time control and the discrete task allocation. The real time control laws are in charge of the correct execution of the tasks assigned by the reallocation algorithm respecting constraints in the connectivity range, the collision avoiding and the full completion of each task. The considered tasks are exploration of the mission environment, search and identification of victims, delivery of medical supplies to victims unable to move and evacuation of victims capable to move. During the development of each task, the robots take routes optimized considering distance metrics based on the breath-first search algorithm and an exploration algorithm for non-convex environments. In order to assign the tasks to the robots thorough the mission, we present an optimized task reallocation algorithm focused on the minimization of the time required to attend all the victims in the mission environment. This algorithm allows to assign each of the robots to an appropriate task considering that the robots may differ in the capability of completing each task as well as in their moving capabilities. This complete framework allows a team of autonomous robots to bring a valuable assistance in a search and rescue situation and its behavior is presented in a non-trivial simulation scenario.