Tamil Nadu recorded 30.62 per cent voting till 11am in 38 Lok Sabha constituencies of the state, with Chief Minister K Palaniswami and DMK chief M K Stalin among the early voters.
Chief Electoral Officer Satyabrata Sahoo said polling has been peaceful until now and issues like technical glitches in some locations are being addressed.
"Polling has been very peaceful," he said.
He said the state has recorded 30.62 per cent voting till 11am, with Arani registering the highest of 36.51 and Central Chennai the minimum of 22.89 per cent.
Giving information about voting for bypolls in 18 assembly segments, he said it ranged between 28 to 30 per cent and added more inputs are being collated.
South Chennai has recorded 23.87 per cent, North Chennai 23.36 per cent and Madurai 25.41 per cent, he added.
He said soon after the mock polls by around 6am, as many as 305 EVMs and 525 VVPATs were changed - spread over 66,167 polling stations - across the state over technical issues. Even if voters did not have the voter''s slip they could still vote since it was not one of the 12 documents mandated for voting.
The slips were only for the purpose of identifying the elector''s polling station and their serial number on poll rolls, he said.
Palaniswami and Stalin waited in queue at Edappadi in Salem district and Chennai, respectively, and cast their votes.
After casting his vote, MK Stalin alleged that there has been distribution of cash and accused the Election Commission of being an "ally" of central and state governments.
Union minister Pon Radhakrishnan, DMK's Dayanidhi Maran and Kanimozhi, and Karti Chidambaram of Congress are among key contenders.
Radhakrishnan told reporters in Kanyakumari: "This is a massive democratic festival which will decide the fate of India. I have exercised my franchise... A silent revolution is happening." AIADMK leader and state minister D Jayakumar said 13 per cent voting in the morning "is a joyous thing."
"This shows there is a wave for Amma and MGR," he said, exuding confidence that the AIADMK-BJP combine will emerge victorious.
Amma Makkal Munnetra Kazhagam leader TTV Dhinakaran alleged "malfunctioning of EVMs is an achievement of the Modi government."
CPI national secretary D Raja expressed confidence that people were voting for the DMK-led alliance in Tamil Nadu as they wanted to see the end of the BJP government at the Centre.
Dayanidhi Maran voted here along with his family members.
Besides 38 of the total 39 Lok Sabha seats in the state, excluding Vellore, bypolls to 18 assembly segments are also underway.
Polling stations were teeming with enthusiastic voters even before 7am when polling began and Chief Minister Palaniswami was among the early electors in his native Salem district.
While senior Congress leader P Chidambaram voted at Kandanur in Sivaganga district, AMMK leader TTV Dhinakaran excised his franchise along with his family here.
Top actor Rajinikanth and popular stars Vijay and Ajith Kumar voted in Chennai.
BJP's Tamil Nadu unit chief Tamilisai Soundararjan and actor and Makkal Needhi Maiam president Kamal Haasan also cast their votes here.
DMDK chief Vijayakanth, his wife and party leader Premalatha and Pattali Makkal Katchi chief S Ramadoss voted in Chennai and Tindivanam respectively.
The state's electorate is 5.84-crore (after deducting the 14.26 lakh voters in Vellore) strong.
Adequate security arrangements, with the deployment of over 160 companies of central police forces and one lakh state police personnel, have been made.
In the run-up to the polls, election authorities had seized over Rs 129-crore cash, gold and other precious metals with a total value of over Rs 284 crore from all over the state.
Tamil Nadu has a total of 67,720 polling stations and 7,780 booths have been categorised as critical and vulnerable where more Central Armed Police Forces personnel, and micro-observers were deployed. Measures like webcasting and videographing of proceedings are also in place.
As many as 1,50,302 ballot units, 89,160 control units and 94,653 VVPAT which allows the electors to cross check the votes they have cast for seven seconds are available.
Every constituency has one all-woman polling station.
While polling will be held between 7am and 6pm in 37 constituencies, it has been extended by two hours until 8pm in Madurai Lok Sabha segment, due to the Chithirai festival, which marks the grand entry of Lord Kallazhagar into the Vaigai river.
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