A clash between BJP and TMC workers on Sunday left eight persons injured in Dumrut village in Birbhum district where polling is underway, police said.
Three workers from both sides were arrested, they said.
BJP has claimed all the injured as their supporters.
Tension also prevailed at Sian village under Nanoor constituency in Birbhum and at Kankartala village under Dubrajpur constituency with the Forward Bloc alleging that their agents were threatened by the Trinamool Congress.
Reports from north Bengal, where polls are being held in six districts of Alipurduar, Jalpaiguri, Darjeeling, Uttar Dinajpur, Dakshin Dinajpur, Malda besides Birbhum in South Bengal, said non-functioning EVMs caused delays in beginning the polling process as voters waited patiently in queue.
The weather being cloudy however, provided the voters reprieve in north Bengal.
Reports from Malda said seven EVMs failed to function at Englishbazar, Chanchol and Manikchak as polling began at 7 AM delaying voting by an hour.
In Jalpaiguri, voting was stalled temporarily at a booth in Jalpaiguri Sadar as the VVPAT did not function, polling officials said.
Four EVMs — two at Jalpaiguri Sadar constituency and two at Rajganj — did not function properly delaying polling.
In Darjeeling district, a malfunctioning EVM resulted in a two hour delay as polling began in the morning at Matigara-Naxalbari (SC) assembly constituency, polling officials said.
Birbhum district in South Bengal where elections are also being held reported malfunctioning of EVMs in three booths at Karidhya under Suri Assembly constituency.
In Malda, a presiding officer in booth no: 163 in Englishbazar assembly segment was removed after the CPI(M) complained that the officer was allegedly working in favour of Trinamool Congress and allowing impersonation of votes.
The District Election Officer has ordered his removal and replacement.
In Saithia assembly constituency, a polling officer in booth no: 13 Abhimanyu Pal was taken ill. Polling, however, was not affected, reports said.
In Jalpaiguri district, the CPI(M) has complained that their polling agent was not being allowed to enter a booth in Rajganj (SC) constituency by Trinamool Congress workers, a charge denied by the latter.
In an incident at Raigunj in North Dinajpur district, a makeshift tent of the Congress was vandalised on poll eve, North Dinjapur Congress general secretary Pabitra Chandra said, adding that they had informed the police and EC today.
He blamed the Trinamool Congress for the incident.