Amid the backdrop of growing violence in the run-up to the Thirumangalam by-poll in January, the Election Commission has decided to seal off the constituency after campaigning comes to an end on January 7 to ensure a free and fair poll.The ban on entry into the area would be applicable to the campaign leaders of all parties including ministers who are not registered voters of the constituency, said EC officials.There are 26 candidates in the fray for the by-poll, necessitated by the death of sitting MDMK MLA, Veera Elavarasan. The directive from the Chief Electoral Officer Naresh Gupta comes at a time when parties filed complaints with the election officials, trading charges of malpractices and large-scale violence. The campaign took a violent turn when a group of supporters belonging to the ruling DMK allegedly attacked an AIADMK campaign convoy, following charges that the Opposition camp was distributing money to voters at several areas in the constituency. The Opposition AIADMK and alliance partners MDMK and CPM have, in turn, levelled allegations that the ruling party unleashed violence upon their cadre involved in campaigning even as the police stood by.The campaign will reach its crescendo during the first week of 2009 when party stalwarts, including Chief Minister M Karunanidhi and Opposition leader J Jayalalithaa, will arrive in the area to canvas for their candidates - Latha Adhiyaman and M Muthuramalingam respectively. DMDK founder, actor-politician Vijayakanth will be another prominent campaigner.Though insignificant in terms of changing equations in the Assembly, the by-election is being contested in full strength by both camps.