The condition of senior CPI(M) leader Anil Biswas remained critical on Sunday morning after he was operated upon following a cerebral attack on Saturday evening.
Biswas, a politburo member of the left party, was under constant observation, doctors attending on him said on Sunday.
Biswas, the secretary of CPI(M) West Bengal unit, was rushed to a private nursing home around 9 pm Saturday after he sufferred brain haemorrhage at home.
The CPI(M) convened an urgent meeting this morning cancelling all its poll related programmes to take stock of the situation, party sources said.
Chief Minister Buddahadev Bhattacharjee, who was scheduled to start campaigning for next month's assembly election at a public meeting on Sunday, has also cancelled the programme and rushed to the party office.