The counting of votes of R K Nagar Assembly constituency was halted for about 15 minutes after clash erupted between the All India Anna Dravida Munnetra Kazhagam (AIADMK) and party's sidelined leader TTV Dhinakaran's supporters outside Queen Mary's college.
Chennai district Electoral Officer said, "Police have restored peace, nothing alarming. The compilation of second round of (counting of votes) is going on."
The result for R K Nagar Assembly constituency is expected to be out by afternoon, and security has been beefed up outside the vote-counting centers.
On December 21, the voting at 258 polling stations took place peacefully under heavy security, which included 2,500 state police personnel and 15 companies of Central Armed Police Forces guarding the centres.
The key candidates in the fray are E Madhusudhanan from AIADMK, sidelined AIADMK leader T T V Dhinakaran, who is contesting as an independent, N Maruthu Ganesh from DMK and Karu Nagarajan from BJP.
The contest is primarily between AIADMK and Congress-backed DMK, who usually enjoy the constituency's mandate.
The bypoll was necessitated after the death of former chief minister Jayalalithaa last year in December, and is speculated to be the litmus test for the leadership of E Panneerselvam and K Palaniswami who took over the reins of AIADMK after her.
After Jayalaithaa's death, the faction was shattered into warring factions until Panneerselvam and Palaniswami joined hands and sidelined the now jailed general secretary V K Sasikala and his nephew Dhinakaran.
Both Sasikala-Dhinakaran camp and EPS-OPS camp staked claim over the party name and its 'two leaves' symbol, which was ultimately allotted to the latter by the Election Commission.
The election was earlier scheduled on April 12 but was cancelled following allegations that sums of money were distributed by the Sasikala-led faction in a vote-for-cash scam.
Few days ahead of the election, DMK working president made fresh allegations against AIADMK of bribing voters in the constituency.
A day before the election, another controversy erupted after disqualified AIADMK MLA P Vetrivel released a 20-second video clip of Jayalalithaa of when she was admitted in a hospital.
The move which added fuel to the controversy surrounding her death received heavy condemnation from rival party leaders who accused Vetrivel of using the clip for political gains in poll-bound RK Nagar.
-ANI