Opposition lodged complaints against alleged distribution of money by the AIADMK's Sasikala faction.
Around Rs 15 lakh was seized and 28 persons were arrested on Wednesday for their alleged roles in various incidents of money distribution to voters and violence in the run up to the April 12 RK Nagar assembly bypoll.
The day also saw the Election Commission ordering transfer of 22 police officials, including two IPS officers, out of RK Nagar even as the opposition parties lodged complaints with Tamil Nadu Chief Electoral Officer Rajesh Lakhoni against the alleged distribution of money to voters by the AIADMK's VK Sasikala faction.
Authorities said seizure of Rs 14.92 lakh was made by EC's flying squads and static surveillance teams in RK Nagar where bypoll was necessitated due to former Chief Minister J Jayalalithaa's death.
While three AIADMK activists (VK Sasikala's Amma faction) were arrested for allegedly attacking DMK cadres over a row, 25 others were arrested on the basis of 15 cases registered for alleged distribution of money to voters, police said.
The attack on DMK men was over a row related to the alleged money distribution, they added.
Meanwhile, videos of alleged money distribution in RK Nagar and markings made in the area to facilitate it are doing the rounds in social media and messaging app Whatsapp.
DMK working president MK Stalin visited a hospital where party cadres were admitted and alleged that Dinakaran-led AIADMK faction was trying to buy democracy using money power.
Speaking to reporters, he said DMK was preparing to legally deal with the matter, besides taking it up with poll authorities.
Commenting on the alleged money distribution, PMK chief Ramadoss demanded countermanding of RK Nagar bypoll and said it should be held after the cash distribution's impact faded.
The bypoll should be held by drafting officers only from outside Tamil Nadu and by deploying Central police forces, he said.
EC replaced Additional Police Commissioner (North) MC Sarangan with H M Jayaram (now IGP, Operations) besides 21 other police personnel.
Meanwhile DMK Rajya Sabha MP, RS Barathi in a petition to Chief Electoral Officer Rajesh Lakhoni said, "The ruling party (Dinakaran faction) is planning to continue the illegal distribution of money to voters. We, herewith, enclose proof of the illegal distribution of money." He demanded steps to stop it.
Former Minister KP Munusamy of O Panneerselvam-led faction too petitioned the CEO on the matter.