Independent mayor candidate Siddikur Rahman gave an undertaking at Rajshahi deputy election commissioner's office yesterday that he would no more violate election rules by using loudspeakers beyond the officially fixed time limit.Election officials along with police seized a three-wheeler and loudspeakers while those were being used for campaigning for Siddikur Rahman after 8 pm Saturday night, which is prohibited.Siddikur Rahman was then summoned to the deputy election commissioner's office. He gave in writing that he would never use loudspeakers on streets violating the code of conduct and abide by other polls rules.However, sources at the election office said they received many such allegations of violation of code of conduct. In most cases, they warn the candidates through letters.Rajshahi city Awami League (AL) secretary and Nagorik Committee candidate AHM Khairuzzaman Liton, Progressive Development Party (PDP) convenor Raihanur Rahman and several counsilors have already given warning for violating the code, the officials said.Visiting the city areas yesterday, big colourful banners seeking vote were seen though these are prohibited as per electoral law. A 25-feet banner was seen on both sides of the over-bridge in front of RDA market, seeking vote for mayoral candidate Masudul Haque Dulu, president of Rajshahi city AL. BNP's Mosaddek Hossain Bulbul and AL's AHM Khairuzzaman Liton were also seen using coloured banners in campaign processions.Deputy Election Commissioner Sayed Muhammad Musa said they were warning candidates for first time violation as the rules are quite new.“If we find candidates violation rules again, we will take action. Warning is also an action… cases of serious offences are separate”, he said.