No untoward incident was reported from any part of the state, but snags in electronic voting machines led to delays in the polling process in some booths, Kundra said.
Forty-two VVPATs, 25 ballot units and 19 control units were being replaced in various polling stations, the CEO stated.
A total of 7,70,395 voters, including 3,94,897 women, would decide the fate of 209 candidates, including Chief Minister Lal Thanhawla, who is contesting from two seats -- Serchhip and Champai South.
While Thanhawla is seeking a third consecutive term in the state, the BJP, which failed to open its account in 2013 elections, is looking to uproot the Congress in its last bastion in the northeast.
Long queues of enthusiastic voters were seen outside many polling stations early in the day.
Former chief minister and opposition Mizo National Front (MNF) chief Zoramthanga was among the first ones to exercise franchise at 7 am.
Zoramthanga cast his vote at Ramhlun polling booth in Aizawl North-II constituency.
Kundra said Bru voters from six relief camps in North Tripura district are arriving in batches at Kanhmun village, along the Mizoram-Tripura border, where 15 temporary polling stations have been erected.
The voters had to walk around 500 metres from the inter-state border to reach the polling stations, where members of local civil societies welcomed them with pork curry.
The CEO expressed hope that the turnout of Bru voters would be "substantial".
"The people of Kanhmun village in Mamit district have erected a welcome gate at the border, where the Bru voters were being greeted on their arrival," Kundra said.
Forty-seven of the 1,179 polling booths have been classified as "critical" and as many as "vulnerable" by the Election Commission.
Ten polling booths, mostly in South Mizoram's Lawngtlai and Lunglei districts, are inaccessible by vehicles.
Election office sources said 40 companies of Central Armed Police Forces, in addition to the state police, have been deployed to ensure free and fair polls.
Each constituency has a polling booth, named after a pink flower 'Dingdi', exclusively for women voters. These booths have women polling officials and security personnel.
While the ruling Congress and the main opposition MNF are contesting all 40 seats, the BJP has fielded candidates in 39 constituencies.
Zoram People's Movement (ZPM), a conglomerate of two political parties -- the Zoram Nationalist Party (ZNP) and Mizoram People's Conference (MPC) -- and five other groups, are in the fray for 35 seats.
The National People's Party and the Nationalist Congress Party are contesting eight seats and five seats respectively.
Six independents are also in the fray.
In 2013 elections, the Congress had won 34 seats, while its main opponent, the MNF, got five and the MPC bagged one seat.
Borders with neighbouring countries -- Myanmar and Bangladesh -- and states -- Tripura, Assam and Manipur -- have been sealed since Sunday in view of the polls.