The EC has also not disclosed to the public the actual amount seized, Stalin said.
In light of the incident, he also called for disqualification of AIADMK candidate E.Madhusudhanan.
"In support of Mr. E.Madhusudhanan, AIADMK candidate, the distribution of money has happened in the entire constituency of No.11, Dr. Radhakrishnan Nagar Assembly Constituency in Tamil Nadu and hence, he must be disqualified forthwith," the letter stated.
The letter further stated that the persons caught by the DMK have been freed by the police without registering a complaint, and that the "Election Commission officials have deliberately failed in discharging their duty".
Stalin further alleged that the ruling party has been paying Rs.6,000 to each voter as bribe in the current bye-election and was "going out to any extent to bribe the voters in the said constituency," and added that "Election commission is not in a position to curb the said illegalities primarily due to the official nexus with the perpetrators of the crime".
"AIADMK office bearers, State Ministers, AIADMK's MLAs and MPs are personally involved in distribution of money. They use their party men brought from various districts, to distribute money," the letter further read.
The RK Nagar bypoll, necessitated after the death of former Chief Minister J Jayalalithaa, was earlier scheduled for April 12, but was cancelled following allegations that sums of money were distributed in a vote-for-cash scam.
Counting of the votes will be held on December 24.