1. A method for tracking interacting objects comprising: acquiring, with at least one sensor, at least two images associated with at least two time instances; generating, with at least one processor, image data from the at least two images; applying, with the at least one processor, an extended Probability Occupancy Map (POM) algorithm to the image data to obtain probability of occupancy for a container class of potentially interacting objects, probability of occupancy for a containee class of the potentially interacting objects, and a size relationship of the potentially interacting objects, over a set of discrete locations on a ground plane for each time instance; and estimating, with the at least one processor, trajectories of at least one object belonging to each of the two classes by determining a solution of a tracking model on the basis of the occupancy probabilities and a set of rules describing the interaction between objects of different or the same classes.