A combination of a discrete particle code with elastic particle interactions and the possibility to fracture was coupled with the numerical model "Elle" in order to study fracture development in complex layered and polycrystalline materials. A number of simulations have been carried out to test the behaviour of fractures in the model and the developing patterns. The model produces realistic behaviour and spacing of mode I fractures during layer parallel extension and a theoretically predicted transition from mode I to mode II fractures during layer parallel compression. The behaviour of the model during pure shear deformation is also realistic and shows an expected initial development of mode I fractures due to low tensile strength of the material and a later propagation of shear fractures along which slip takes place. Fracture patterns around expanding grains produce isotropic patterns that are similar to dielectric breakdown that has similarities to natural fracture patterns. We conclude therefore that the model can be used to simulate brittle behaviour of materials and has a large applicability in future research.