Condoling the death of four people in firing by central forces in Cooch Behar, Prime Minister Narendra Modi Saturday requested the Election Commission to take stern action against those responsible for the incident and blamed the ruling TMC for perpetrating violence during the polls.

He also accused Chief Minister Mamata Banerjee of instigating people against the central forces.

"What happened in Cooch Behar is unfortunate and sad.

I extend my condolences to the bereaved families and urge the Election Commission to take stern action against those responsible for the incident.

"Mamata Didi and her TMC goons have become jittery because of ground swell of support for BJP," Modi told an election rally at Siliguri in North Bengal.

Four persons were killed when CISF personnel opened fire allegedly after coming under attack from locals, who "attempted to snatch their rifles" in Cooch Behar district.

The incident took place in the Sitalkuchi area when voting was underway, a senior district police officer said.

"Didi, this violence, the tactic of instigating people to attack the security forces, the tactic of obstructing the polling process will not protect you. You have to go out of power. Didi is asking people to attack and gherao security forces who are here to protect the rights of the people of the state," he said.

Attacking Mamata over the culture of violence and "tolabaji" (extortion), Modi said people of Bengal had made up their mind to defeat the TMC.

"Didi, you don't preside over the destiny of the people of Bengal, they are not your 'jagir' (fiefdom)," he said.

North Bengal, he said, was critical to national security which has been undermined due to appeasement politics of Mamata.

Reaching out to the numerically strong Dalit Rajbongshi and Matua communities, Modi said the TMC insults them, and claimed a party leader was shown in a video likening the scheduled caste people to beggars.