At a Kolkata hospital, a man injured in the communal violence was declared dead on Thursday, three days after he was brought from the trouble-torn town in a critical condition. Kartik Ghosh, 60, had knife wounds to his neck.

As news of his death spread, a row erupted at the hospital gates between workers of the Trinamool and the BJP over which party Mr Ghosh belonged to. The police struggled to disperse the two groups that clashed and urged top BJP leaders, including state BJP chief Dilip Ghosh and national general secretary Kailash Vijayvargiya, to leave the spot.

Tensions are up in Basirhat and adjoining areas in North 24 Parganas where there has been violence since Monday after a Facebook post by a teen about Prophet Mohammad angered Muslims. Opposition parties the BJP, the Congress and the CPM have said they will go to the trouble areas today to call for peace.

Till reports last came in on Thursday evening, the angry groups were out in Basirhat, blocking the main road through the town at many places. BSF soldiers failed to lift the road blocks. Women said they would not move till they were guaranteed safety.

Trinamool legislator Dibyendu Biswas, a former India footballer and elected for the first time in assembly elections last year, has been summoned by his party chief and West Bengal Chief Minister Mamata Banerjee or his alleged actions in Basirhat.

The violence began on Monday in Baduria, about 20 km from Basirhat, and swept through other towns. Mobs set police vehicles on fire, threw bombs and blocked roads and rail tracks.

Twenty one people have been injured in the violence since Monday night and of them eight, including Mr Ghosh, were shifted to Kolkata's RG Kar hospital in a critical condition. The violence peaked on Tuesday and simmered to an uneasy calm on Wednesday after the BSF began patrolling the area, before erupting again on Thursday.

The Centre sent 400 personnel of the BSF on Tuesday to help maintain peace, but Chief Minister Mamata Banerjee turned down the offer of additional troops on Thursday, saying the state police could handle the situation.

The BJP says more than 2,000 Muslims attacked Hindu families in the North 24 Parganas district and its offices in several places were set on fire. It has accused Ms Banerjee of protecting anti-social elements and said the situation is a fallout of her appeasement of the Muslim community which supports her party. "Total administration failure in Bengal," said Mr Vijayvargiya who landed in Kolkata on Thursday.