Kolkata: Under tight security, over 78 percent of the around 1.24 crore electorate braved the sweltering heat and oppressive humidity to cast their votes for 53 constituencies in the fifth and penultimate phase of the West Bengal assembly polls on Saturday.

Stray incidents of violence were reported, but the opposition parties acknowledged the polling was overall peaceful.

Since 7 a.m., when polling began, large queues of voters were seen outside almost all the booths for 31 constituencies in South 24 Parganas and 18 in Hooghly districts besides four in South Kolkata - covering a region which has for years been a citadel of the ruling Trinamool Congress.

The elections continued beyond the scheduled time of 6 p.m. but the poll panel could only provide the voting figures till 5 p.m.

"Poll percentage till 5 p.m. was 78.25 percent overall. In Hooghly it was 78.98 percent, in Kolkata South, 63.10 percent and in South 24 Parganas, 79.69 percent," said state chief electoral officer Sunil Gupta.

Gupta said altogether 186 people were arrested, of whom 177 were taken into custody under preventive sections, and nine others on specific charges.

A first information report was filed against assembly Deputy Speaker and Trinamool Congress candidate from Satgachia of South 24 Parganas, Sonali Guha after she was caught by TV cameras instructing over phone to "thrash CPI-M agent from a booth".

The poll panel removed two presiding officers in Hooghly district - one from Tarakeswar constituency for allegedly helping voters for casting their votes and another from Arambagh for allegedly allowing unauthorised persons to enter the booth and help voters to cast their franchise, Gupta said.

"FIRs have been lodged against them," he said.

Five Trinamool supporters were injured, two of them receiving gunshot wounds, in a clash with Communist Party of India-Marxist (CPI-M) supporters at Gourdha in Baruipur East constituency of South 24 Parganas, said Additional Director General of Police (Law and Order) Anuj Sharma.

In Bhangore constituency of the same district, four people were injured in a clash at Saturia area. Another person sustained injury in Natapukur area of the same seat.

Four others were injured during a clash between Trinamool and Revolutionary Socialist Party workers at Bagankhali of Basanti constituency in South 24 Parganas.

However, there was almost a festive atmosphere in the booths of south Kolkata, with the central police forces keeping a strict watch to ensure free and fair polls.

A clutch of celebrities - actresses Roopa Ganguly, Moon Moon Sen and her daughters Riya and Raima, Rituparna Sengupta, Indrani Haldar, veteran actor Ranjit Mullick, and former Indian cricket captain Sourav Ganguly - expressed their democratic choice.

Nearly 1.24 crore voters across 14,642 polling stations, including 77 auxiliary booths, were eligible to decide the fate of 349 candidates -- 43 of them female.

The Trinamool and the Bharatiya Janata Party (BJP) are contesting in all the seats in this phase.

The Left Front, which has tied up with the Congress, is in the fray in 37 seats - CPI-M (31), All India Forward Bloc (three), Revolutionary Socialist Party (two) and Communist Party of India (one). The Congress has 14 candidates in the contest, with the alliance supporting Janata Dal (United) and an independent in one seat each.

In the 2011 assembly polls, the Trinamool had captured 46 of these seats. The LF had won only six - CPI-M four, and the RSP and the FB one each. The Socialist Unity Cetre of India-Communist had bagged one.

Among the political big shots who exercised their franchise were Chief Minister and Trinamool supremo Mamata Banerjee and her predecessor and Marxist veteran Buddhadeb Bhattacharjee.

All eyes were on south Kolkata's Bhabanipur, where Banerjee -- seeking re-election -- is facing a challenge from Left Front-backed Congress nominee Deepa Dasmunshi and Netaji Subhas Chandra Bose's grandnephew Chandra Kumar Bose of the BJP.

Accusing the central security forces of "terrorising" the people, Trinamool vice president Mukul Roy said: "In some places, they even went beyond their mandate."

On the other hand, CPI-M politburo member Mohammed Salim congratulated the EC and the entire election machinery for taking steps to ensure people could exercise their right freely and fairly.

But he pointed out that there were some sporadic incidents like assault on polling agents, booth jamming and voter intimidation.

Congress leader Abdul Mannan said the polls were overall peaceful.

After Saturday's polls, elections have been held in 269 of the 294 constituencies in the state.

The remaining 25 will vote in the sixth and final phase on May 5. The vote count will be held on May 19.