The Kerala Police on Monday rushed reinforcements from neighbouring districts to Kannur, to contain the sporadic political violence in the wake of the killing of a CPI(M) man, KP Jijesh, on Sunday.Jijesh, who was hacked and stabbed to death on a street allegedly by RSS men, is the fourth CPM worker to be killed in recent weeks in the politically volatile district, which trails a long and bitter record of tit-for-tat killing and maiming of scores of workers on the two sides — and occasionally, of the Congress.Police patrols were attacked by mobs wielding country bombs and swords on Monday and a sub inspector and two constables have been injured. Offices of the CPI(M), BJP-RSS and also the Congress were damaged in mob attacks in several parts, even as an all-party peace meet pleaded for calm.Police sources said combing operations all over the area on Monday yielded caches of weapons including hatchets, swords and country bombs, and a few arrests have been made. The raids have been continuing as of late evening, and the Home Minister Kodiyeri Balakrishnan has rushed to the affected areas.