(KUNA) -- Fierce clashes took place in different parts in northern Baghdad Saturday but no casualties were reported, Iraqi police said. A source at the police told KUNA the confrontations erupted between armed groups and militias in the northern districts of the Iraqi capital. The gunmen used light weapons and rocket propelled grenades (RPGs), according to the source, resulting in setting three houses on fire. It is unknown whether there were people inside the houses.The fact clashes were very heavy, said the source, did not allow security forces to know the number of casualties among both parties. Iraqi army forces intervened to restore order in the northern areas, said the source. The clashes occurred before Prime Minister Nouri Al-Maliki announces his national conciliation plan before the National Assembly on Sunday. The plan aims at cracking down on sectarian violence.